JDK14/Java14源码在线阅读
/*
* Copyright (c) 1999, 2019, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2012, 2019 SAP SE. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
// According to the AIX OS doc #pragma alloca must be used
// with C++ compiler before referencing the function alloca()
#pragma alloca
// no precompiled headers
#include "jvm.h"
#include "classfile/classLoader.hpp"
#include "classfile/systemDictionary.hpp"
#include "classfile/vmSymbols.hpp"
#include "code/icBuffer.hpp"
#include "code/vtableStubs.hpp"
#include "compiler/compileBroker.hpp"
#include "interpreter/interpreter.hpp"
#include "logging/log.hpp"
#include "logging/logStream.hpp"
#include "libo4.hpp"
#include "libperfstat_aix.hpp"
#include "libodm_aix.hpp"
#include "loadlib_aix.hpp"
#include "memory/allocation.inline.hpp"
#include "memory/filemap.hpp"
#include "misc_aix.hpp"
#include "oops/oop.inline.hpp"
#include "os_aix.inline.hpp"
#include "os_share_aix.hpp"
#include "porting_aix.hpp"
#include "prims/jniFastGetField.hpp"
#include "prims/jvm_misc.hpp"
#include "runtime/arguments.hpp"
#include "runtime/atomic.hpp"
#include "runtime/extendedPC.hpp"
#include "runtime/globals.hpp"
#include "runtime/interfaceSupport.inline.hpp"
#include "runtime/java.hpp"
#include "runtime/javaCalls.hpp"
#include "runtime/mutexLocker.hpp"
#include "runtime/objectMonitor.hpp"
#include "runtime/os.hpp"
#include "runtime/osThread.hpp"
#include "runtime/perfMemory.hpp"
#include "runtime/sharedRuntime.hpp"
#include "runtime/statSampler.hpp"
#include "runtime/stubRoutines.hpp"
#include "runtime/thread.inline.hpp"
#include "runtime/threadCritical.hpp"
#include "runtime/timer.hpp"
#include "runtime/vm_version.hpp"
#include "services/attachListener.hpp"
#include "services/runtimeService.hpp"
#include "utilities/align.hpp"
#include "utilities/decoder.hpp"
#include "utilities/defaultStream.hpp"
#include "utilities/events.hpp"
#include "utilities/growableArray.hpp"
#include "utilities/vmError.hpp"
// put OS-includes here (sorted alphabetically)
#include <errno.h>
#include <fcntl.h>
#include <inttypes.h>
#include <poll.h>
#include <procinfo.h>
#include <pthread.h>
#include <pwd.h>
#include <semaphore.h>
#include <signal.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/ipc.h>
#include <sys/mman.h>
#include <sys/resource.h>
#include <sys/select.h>
#include <sys/shm.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/sysinfo.h>
#include <sys/systemcfg.h>
#include <sys/time.h>
#include <sys/times.h>
#include <sys/types.h>
#include <sys/utsname.h>
#include <sys/vminfo.h>
#include <sys/wait.h>
// Missing prototypes for various system APIs.
extern "C"
int mread_real_time(timebasestruct_t *t, size_t size_of_timebasestruct_t);
#if !defined(_AIXVERSION_610)
extern "C" int getthrds64(pid_t, struct thrdentry64*, int, tid64_t*, int);
extern "C" int getprocs64(procentry64*, int, fdsinfo*, int, pid_t*, int);
extern "C" int getargs(procsinfo*, int, char*, int);
#endif
#define MAX_PATH (2 * K)
// for timer info max values which include all bits
#define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
// for multipage initialization error analysis (in 'g_multipage_error')
#define ERROR_MP_OS_TOO_OLD 100
#define ERROR_MP_EXTSHM_ACTIVE 101
#define ERROR_MP_VMGETINFO_FAILED 102
#define ERROR_MP_VMGETINFO_CLAIMS_NO_SUPPORT_FOR_64K 103
// excerpts from systemcfg.h that might be missing on older os levels
#ifndef PV_7
#define PV_7 0x200000 /* Power PC 7 */
#endif
#ifndef PV_7_Compat
#define PV_7_Compat 0x208000 /* Power PC 7 */
#endif
#ifndef PV_8
#define PV_8 0x300000 /* Power PC 8 */
#endif
#ifndef PV_8_Compat
#define PV_8_Compat 0x308000 /* Power PC 8 */
#endif
#ifndef PV_9
#define PV_9 0x400000 /* Power PC 9 */
#endif
#ifndef PV_9_Compat
#define PV_9_Compat 0x408000 /* Power PC 9 */
#endif
static address resolve_function_descriptor_to_code_pointer(address p);
static void vmembk_print_on(outputStream* os);
////////////////////////////////////////////////////////////////////////////////
// global variables (for a description see os_aix.hpp)
julong os::Aix::_physical_memory = 0;
pthread_t os::Aix::_main_thread = ((pthread_t)0);
int os::Aix::_page_size = -1;
// -1 = uninitialized, 0 if AIX, 1 if OS/400 pase
int os::Aix::_on_pase = -1;
// 0 = uninitialized, otherwise 32 bit number:
// 0xVVRRTTSS
// VV - major version
// RR - minor version
// TT - tech level, if known, 0 otherwise
// SS - service pack, if known, 0 otherwise
uint32_t os::Aix::_os_version = 0;
// -1 = uninitialized, 0 - no, 1 - yes
int os::Aix::_xpg_sus_mode = -1;
// -1 = uninitialized, 0 - no, 1 - yes
int os::Aix::_extshm = -1;
////////////////////////////////////////////////////////////////////////////////
// local variables
static volatile jlong max_real_time = 0;
static jlong initial_time_count = 0;
static int clock_tics_per_sec = 100;
static sigset_t check_signal_done; // For diagnostics to print a message once (see run_periodic_checks)
static bool check_signals = true;
static int SR_signum = SIGUSR2; // Signal used to suspend/resume a thread (must be > SIGSEGV, see 4355769)
static sigset_t SR_sigset;
// Process break recorded at startup.
static address g_brk_at_startup = NULL;
// This describes the state of multipage support of the underlying
// OS. Note that this is of no interest to the outsize world and
// therefore should not be defined in AIX class.
//
// AIX supports four different page sizes - 4K, 64K, 16MB, 16GB. The
// latter two (16M "large" resp. 16G "huge" pages) require special
// setup and are normally not available.
//
// AIX supports multiple page sizes per process, for:
// - Stack (of the primordial thread, so not relevant for us)
// - Data - data, bss, heap, for us also pthread stacks
// - Text - text code
// - shared memory
//
// Default page sizes can be set via linker options (-bdatapsize, -bstacksize, ...)
// and via environment variable LDR_CNTRL (DATAPSIZE, STACKPSIZE, ...).
//
// For shared memory, page size can be set dynamically via
// shmctl(). Different shared memory regions can have different page
// sizes.
//
// More information can be found at AIBM info center:
// http://publib.boulder.ibm.com/infocenter/aix/v6r1/index.jsp?topic=/com.ibm.aix.prftungd/doc/prftungd/multiple_page_size_app_support.htm
//
static struct {
size_t pagesize; // sysconf _SC_PAGESIZE (4K)
size_t datapsize; // default data page size (LDR_CNTRL DATAPSIZE)
size_t shmpsize; // default shared memory page size (LDR_CNTRL SHMPSIZE)
size_t pthr_stack_pagesize; // stack page size of pthread threads
size_t textpsize; // default text page size (LDR_CNTRL STACKPSIZE)
bool can_use_64K_pages; // True if we can alloc 64K pages dynamically with Sys V shm.
bool can_use_16M_pages; // True if we can alloc 16M pages dynamically with Sys V shm.
int error; // Error describing if something went wrong at multipage init.
} g_multipage_support = {
(size_t) -1,
(size_t) -1,
(size_t) -1,
(size_t) -1,
(size_t) -1,
false, false,
0
};
// We must not accidentally allocate memory close to the BRK - even if
// that would work - because then we prevent the BRK segment from
// growing which may result in a malloc OOM even though there is
// enough memory. The problem only arises if we shmat() or mmap() at
// a specific wish address, e.g. to place the heap in a
// compressed-oops-friendly way.
static bool is_close_to_brk(address a) {
assert0(g_brk_at_startup != NULL);
if (a >= g_brk_at_startup &&
a < (g_brk_at_startup + MaxExpectedDataSegmentSize)) {
return true;
}
return false;
}
julong os::available_memory() {
return Aix::available_memory();
}
julong os::Aix::available_memory() {
// Avoid expensive API call here, as returned value will always be null.
if (os::Aix::on_pase()) {
return 0x0LL;
}
os::Aix::meminfo_t mi;
if (os::Aix::get_meminfo(&mi)) {
return mi.real_free;
} else {
return ULONG_MAX;
}
}
julong os::physical_memory() {
return Aix::physical_memory();
}
// Return true if user is running as root.
bool os::have_special_privileges() {
static bool init = false;
static bool privileges = false;
if (!init) {
privileges = (getuid() != geteuid()) || (getgid() != getegid());
init = true;
}
return privileges;
}
// Helper function, emulates disclaim64 using multiple 32bit disclaims
// because we cannot use disclaim64() on AS/400 and old AIX releases.
static bool my_disclaim64(char* addr, size_t size) {
if (size == 0) {
return true;
}
// Maximum size 32bit disclaim() accepts. (Theoretically 4GB, but I just do not trust that.)
const unsigned int maxDisclaimSize = 0x40000000;
const unsigned int numFullDisclaimsNeeded = (size / maxDisclaimSize);
const unsigned int lastDisclaimSize = (size % maxDisclaimSize);
char* p = addr;
for (int i = 0; i < numFullDisclaimsNeeded; i ++) {
if (::disclaim(p, maxDisclaimSize, DISCLAIM_ZEROMEM) != 0) {
trcVerbose("Cannot disclaim %p - %p (errno %d)\n", p, p + maxDisclaimSize, errno);
return false;
}
p += maxDisclaimSize;
}
if (lastDisclaimSize > 0) {
if (::disclaim(p, lastDisclaimSize, DISCLAIM_ZEROMEM) != 0) {
trcVerbose("Cannot disclaim %p - %p (errno %d)\n", p, p + lastDisclaimSize, errno);
return false;
}
}
return true;
}
// Cpu architecture string
#if defined(PPC32)
static char cpu_arch[] = "ppc";
#elif defined(PPC64)
static char cpu_arch[] = "ppc64";
#else
#error Add appropriate cpu_arch setting
#endif
// Wrap the function "vmgetinfo" which is not available on older OS releases.
static int checked_vmgetinfo(void *out, int command, int arg) {
if (os::Aix::on_pase() && os::Aix::os_version_short() < 0x0601) {
guarantee(false, "cannot call vmgetinfo on AS/400 older than V6R1");
}
return ::vmgetinfo(out, command, arg);
}
// Given an address, returns the size of the page backing that address.
size_t os::Aix::query_pagesize(void* addr) {
if (os::Aix::on_pase() && os::Aix::os_version_short() < 0x0601) {
// AS/400 older than V6R1: no vmgetinfo here, default to 4K
return 4*K;
}
vm_page_info pi;
pi.addr = (uint64_t)addr;
if (checked_vmgetinfo(&pi, VM_PAGE_INFO, sizeof(pi)) == 0) {
return pi.pagesize;
} else {
assert(false, "vmgetinfo failed to retrieve page size");
return 4*K;
}
}
void os::Aix::initialize_system_info() {
// Get the number of online(logical) cpus instead of configured.
os::_processor_count = sysconf(_SC_NPROCESSORS_ONLN);
assert(_processor_count > 0, "_processor_count must be > 0");
// Retrieve total physical storage.
os::Aix::meminfo_t mi;
if (!os::Aix::get_meminfo(&mi)) {
assert(false, "os::Aix::get_meminfo failed.");
}
_physical_memory = (julong) mi.real_total;
}
// Helper function for tracing page sizes.
static const char* describe_pagesize(size_t pagesize) {
switch (pagesize) {
case 4*K : return "4K";
case 64*K: return "64K";
case 16*M: return "16M";
case 16*G: return "16G";
default:
assert(false, "surprise");
return "??";
}
}
// Probe OS for multipage support.
// Will fill the global g_multipage_support structure.
// Must be called before calling os::large_page_init().
static void query_multipage_support() {
guarantee(g_multipage_support.pagesize == -1,
"do not call twice");
g_multipage_support.pagesize = ::sysconf(_SC_PAGESIZE);
// This really would surprise me.
assert(g_multipage_support.pagesize == 4*K, "surprise!");
// Query default data page size (default page size for C-Heap, pthread stacks and .bss).
// Default data page size is defined either by linker options (-bdatapsize)
// or by environment variable LDR_CNTRL (suboption DATAPSIZE). If none is given,
// default should be 4K.
{
void* p = ::malloc(16*M);
g_multipage_support.datapsize = os::Aix::query_pagesize(p);
::free(p);
}
// Query default shm page size (LDR_CNTRL SHMPSIZE).
// Note that this is pure curiosity. We do not rely on default page size but set
// our own page size after allocated.
{
const int shmid = ::shmget(IPC_PRIVATE, 1, IPC_CREAT | S_IRUSR | S_IWUSR);
guarantee(shmid != -1, "shmget failed");
void* p = ::shmat(shmid, NULL, 0);
::shmctl(shmid, IPC_RMID, NULL);
guarantee(p != (void*) -1, "shmat failed");
g_multipage_support.shmpsize = os::Aix::query_pagesize(p);
::shmdt(p);
}
// Before querying the stack page size, make sure we are not running as primordial
// thread (because primordial thread's stack may have different page size than
// pthread thread stacks). Running a VM on the primordial thread won't work for a
// number of reasons so we may just as well guarantee it here.
guarantee0(!os::is_primordial_thread());
// Query pthread stack page size. Should be the same as data page size because
// pthread stacks are allocated from C-Heap.
{
int dummy = 0;
g_multipage_support.pthr_stack_pagesize = os::Aix::query_pagesize(&dummy);
}
// Query default text page size (LDR_CNTRL TEXTPSIZE).
{
address any_function =
resolve_function_descriptor_to_code_pointer((address)describe_pagesize);
g_multipage_support.textpsize = os::Aix::query_pagesize(any_function);
}
// Now probe for support of 64K pages and 16M pages.
// Before OS/400 V6R1, there is no support for pages other than 4K.
if (os::Aix::on_pase_V5R4_or_older()) {
trcVerbose("OS/400 < V6R1 - no large page support.");
g_multipage_support.error = ERROR_MP_OS_TOO_OLD;
goto query_multipage_support_end;
}
// Now check which page sizes the OS claims it supports, and of those, which actually can be used.
{
const int MAX_PAGE_SIZES = 4;
psize_t sizes[MAX_PAGE_SIZES];
const int num_psizes = checked_vmgetinfo(sizes, VMINFO_GETPSIZES, MAX_PAGE_SIZES);
if (num_psizes == -1) {
trcVerbose("vmgetinfo(VMINFO_GETPSIZES) failed (errno: %d)", errno);
trcVerbose("disabling multipage support.");
g_multipage_support.error = ERROR_MP_VMGETINFO_FAILED;
goto query_multipage_support_end;
}
guarantee(num_psizes > 0, "vmgetinfo(.., VMINFO_GETPSIZES, ...) failed.");
assert(num_psizes <= MAX_PAGE_SIZES, "Surprise! more than 4 page sizes?");
trcVerbose("vmgetinfo(.., VMINFO_GETPSIZES, ...) returns %d supported page sizes: ", num_psizes);
for (int i = 0; i < num_psizes; i ++) {
trcVerbose(" %s ", describe_pagesize(sizes[i]));
}
// Can we use 64K, 16M pages?
for (int i = 0; i < num_psizes; i ++) {
const size_t pagesize = sizes[i];
if (pagesize != 64*K && pagesize != 16*M) {
continue;
}
bool can_use = false;
trcVerbose("Probing support for %s pages...", describe_pagesize(pagesize));
const int shmid = ::shmget(IPC_PRIVATE, pagesize,
IPC_CREAT | S_IRUSR | S_IWUSR);
guarantee0(shmid != -1); // Should always work.
// Try to set pagesize.
struct shmid_ds shm_buf = { 0 };
shm_buf.shm_pagesize = pagesize;
if (::shmctl(shmid, SHM_PAGESIZE, &shm_buf) != 0) {
const int en = errno;
::shmctl(shmid, IPC_RMID, NULL); // As early as possible!
trcVerbose("shmctl(SHM_PAGESIZE) failed with errno=%d", errno);
} else {
// Attach and double check pageisze.
void* p = ::shmat(shmid, NULL, 0);
::shmctl(shmid, IPC_RMID, NULL); // As early as possible!
guarantee0(p != (void*) -1); // Should always work.
const size_t real_pagesize = os::Aix::query_pagesize(p);
if (real_pagesize != pagesize) {
trcVerbose("real page size (" SIZE_FORMAT_HEX ") differs.", real_pagesize);
} else {
can_use = true;
}
::shmdt(p);
}
trcVerbose("Can use: %s", (can_use ? "yes" : "no"));
if (pagesize == 64*K) {
g_multipage_support.can_use_64K_pages = can_use;
} else if (pagesize == 16*M) {
g_multipage_support.can_use_16M_pages = can_use;
}
}
} // end: check which pages can be used for shared memory
query_multipage_support_end:
trcVerbose("base page size (sysconf _SC_PAGESIZE): %s",
describe_pagesize(g_multipage_support.pagesize));
trcVerbose("Data page size (C-Heap, bss, etc): %s",
describe_pagesize(g_multipage_support.datapsize));
trcVerbose("Text page size: %s",
describe_pagesize(g_multipage_support.textpsize));
trcVerbose("Thread stack page size (pthread): %s",
describe_pagesize(g_multipage_support.pthr_stack_pagesize));
trcVerbose("Default shared memory page size: %s",
describe_pagesize(g_multipage_support.shmpsize));
trcVerbose("Can use 64K pages dynamically with shared memory: %s",
(g_multipage_support.can_use_64K_pages ? "yes" :"no"));
trcVerbose("Can use 16M pages dynamically with shared memory: %s",
(g_multipage_support.can_use_16M_pages ? "yes" :"no"));
trcVerbose("Multipage error details: %d",
g_multipage_support.error);
// sanity checks
assert0(g_multipage_support.pagesize == 4*K);
assert0(g_multipage_support.datapsize == 4*K || g_multipage_support.datapsize == 64*K);
assert0(g_multipage_support.textpsize == 4*K || g_multipage_support.textpsize == 64*K);
assert0(g_multipage_support.pthr_stack_pagesize == g_multipage_support.datapsize);
assert0(g_multipage_support.shmpsize == 4*K || g_multipage_support.shmpsize == 64*K);
}
void os::init_system_properties_values() {
#ifndef OVERRIDE_LIBPATH
#define DEFAULT_LIBPATH "/lib:/usr/lib"
#else
#define DEFAULT_LIBPATH OVERRIDE_LIBPATH
#endif
#define EXTENSIONS_DIR "/lib/ext"
// Buffer that fits several sprintfs.
// Note that the space for the trailing null is provided
// by the nulls included by the sizeof operator.
const size_t bufsize =
MAX2((size_t)MAXPATHLEN, // For dll_dir & friends.
(size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR)); // extensions dir
char *buf = NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
// sysclasspath, java_home, dll_dir
{
char *pslash;
os::jvm_path(buf, bufsize);
// Found the full path to libjvm.so.
// Now cut the path to <java_home>/jre if we can.
pslash = strrchr(buf, '/');
if (pslash != NULL) {
*pslash = '\0'; // Get rid of /libjvm.so.
}
pslash = strrchr(buf, '/');
if (pslash != NULL) {
*pslash = '\0'; // Get rid of /{client|server|hotspot}.
}
Arguments::set_dll_dir(buf);
if (pslash != NULL) {
pslash = strrchr(buf, '/');
if (pslash != NULL) {
*pslash = '\0'; // Get rid of /lib.
}
}
Arguments::set_java_home(buf);
if (!set_boot_path('/', ':')) {
vm_exit_during_initialization("Failed setting boot class path.", NULL);
}
}
// Where to look for native libraries.
// On Aix we get the user setting of LIBPATH.
// Eventually, all the library path setting will be done here.
// Get the user setting of LIBPATH.
const char *v = ::getenv("LIBPATH");
const char *v_colon = ":";
if (v == NULL) { v = ""; v_colon = ""; }
// Concatenate user and invariant part of ld_library_path.
// That's +1 for the colon and +1 for the trailing '\0'.
char *ld_library_path = NEW_C_HEAP_ARRAY(char, strlen(v) + 1 + sizeof(DEFAULT_LIBPATH) + 1, mtInternal);
sprintf(ld_library_path, "%s%s" DEFAULT_LIBPATH, v, v_colon);
Arguments::set_library_path(ld_library_path);
FREE_C_HEAP_ARRAY(char, ld_library_path);
// Extensions directories.
sprintf(buf, "%s" EXTENSIONS_DIR, Arguments::get_java_home());
Arguments::set_ext_dirs(buf);
FREE_C_HEAP_ARRAY(char, buf);
#undef DEFAULT_LIBPATH
#undef EXTENSIONS_DIR
}
////////////////////////////////////////////////////////////////////////////////
// breakpoint support
void os::breakpoint() {
BREAKPOINT;
}
extern "C" void breakpoint() {
// use debugger to set breakpoint here
}
////////////////////////////////////////////////////////////////////////////////
// signal support
debug_only(static bool signal_sets_initialized = false);
static sigset_t unblocked_sigs, vm_sigs;
void os::Aix::signal_sets_init() {
// Should also have an assertion stating we are still single-threaded.
assert(!signal_sets_initialized, "Already initialized");
// Fill in signals that are necessarily unblocked for all threads in
// the VM. Currently, we unblock the following signals:
// SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
// by -Xrs (=ReduceSignalUsage));
// BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
// other threads. The "ReduceSignalUsage" boolean tells us not to alter
// the dispositions or masks wrt these signals.
// Programs embedding the VM that want to use the above signals for their
// own purposes must, at this time, use the "-Xrs" option to prevent
// interference with shutdown hooks and BREAK_SIGNAL thread dumping.
// (See bug 4345157, and other related bugs).
// In reality, though, unblocking these signals is really a nop, since
// these signals are not blocked by default.
sigemptyset(&unblocked_sigs);
sigaddset(&unblocked_sigs, SIGILL);
sigaddset(&unblocked_sigs, SIGSEGV);
sigaddset(&unblocked_sigs, SIGBUS);
sigaddset(&unblocked_sigs, SIGFPE);
sigaddset(&unblocked_sigs, SIGTRAP);
sigaddset(&unblocked_sigs, SR_signum);
if (!ReduceSignalUsage) {
if (!os::Posix::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
}
if (!os::Posix::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
}
if (!os::Posix::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
}
}
// Fill in signals that are blocked by all but the VM thread.
sigemptyset(&vm_sigs);
if (!ReduceSignalUsage)
sigaddset(&vm_sigs, BREAK_SIGNAL);
debug_only(signal_sets_initialized = true);
}
// These are signals that are unblocked while a thread is running Java.
// (For some reason, they get blocked by default.)
sigset_t* os::Aix::unblocked_signals() {
assert(signal_sets_initialized, "Not initialized");
return &unblocked_sigs;
}
// These are the signals that are blocked while a (non-VM) thread is
// running Java. Only the VM thread handles these signals.
sigset_t* os::Aix::vm_signals() {
assert(signal_sets_initialized, "Not initialized");
return &vm_sigs;
}
void os::Aix::hotspot_sigmask(Thread* thread) {
//Save caller's signal mask before setting VM signal mask
sigset_t caller_sigmask;
pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
OSThread* osthread = thread->osthread();
osthread->set_caller_sigmask(caller_sigmask);
pthread_sigmask(SIG_UNBLOCK, os::Aix::unblocked_signals(), NULL);
if (!ReduceSignalUsage) {
if (thread->is_VM_thread()) {
// Only the VM thread handles BREAK_SIGNAL ...
pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
} else {
// ... all other threads block BREAK_SIGNAL
pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
}
}
}
// retrieve memory information.
// Returns false if something went wrong;
// content of pmi undefined in this case.
bool os::Aix::get_meminfo(meminfo_t* pmi) {
assert(pmi, "get_meminfo: invalid parameter");
memset(pmi, 0, sizeof(meminfo_t));
if (os::Aix::on_pase()) {
// On PASE, use the libo4 porting library.
unsigned long long virt_total = 0;
unsigned long long real_total = 0;
unsigned long long real_free = 0;
unsigned long long pgsp_total = 0;
unsigned long long pgsp_free = 0;
if (libo4::get_memory_info(&virt_total, &real_total, &real_free, &pgsp_total, &pgsp_free)) {
pmi->virt_total = virt_total;
pmi->real_total = real_total;
pmi->real_free = real_free;
pmi->pgsp_total = pgsp_total;
pmi->pgsp_free = pgsp_free;
return true;
}
return false;
} else {
// On AIX, I use the (dynamically loaded) perfstat library to retrieve memory statistics
// See:
// http://publib.boulder.ibm.com/infocenter/systems/index.jsp
// ?topic=/com.ibm.aix.basetechref/doc/basetrf1/perfstat_memtot.htm
// http://publib.boulder.ibm.com/infocenter/systems/index.jsp
// ?topic=/com.ibm.aix.files/doc/aixfiles/libperfstat.h.htm
perfstat_memory_total_t psmt;
memset (&psmt, '\0', sizeof(psmt));
const int rc = libperfstat::perfstat_memory_total(NULL, &psmt, sizeof(psmt), 1);
if (rc == -1) {
trcVerbose("perfstat_memory_total() failed (errno=%d)", errno);
assert(0, "perfstat_memory_total() failed");
return false;
}
assert(rc == 1, "perfstat_memory_total() - weird return code");
// excerpt from
// http://publib.boulder.ibm.com/infocenter/systems/index.jsp
// ?topic=/com.ibm.aix.files/doc/aixfiles/libperfstat.h.htm
// The fields of perfstat_memory_total_t:
// u_longlong_t virt_total Total virtual memory (in 4 KB pages).
// u_longlong_t real_total Total real memory (in 4 KB pages).
// u_longlong_t real_free Free real memory (in 4 KB pages).
// u_longlong_t pgsp_total Total paging space (in 4 KB pages).
// u_longlong_t pgsp_free Free paging space (in 4 KB pages).
pmi->virt_total = psmt.virt_total * 4096;
pmi->real_total = psmt.real_total * 4096;
pmi->real_free = psmt.real_free * 4096;
pmi->pgsp_total = psmt.pgsp_total * 4096;
pmi->pgsp_free = psmt.pgsp_free * 4096;
return true;
}
} // end os::Aix::get_meminfo
//////////////////////////////////////////////////////////////////////////////
// create new thread
// Thread start routine for all newly created threads
static void *thread_native_entry(Thread *thread) {
thread->record_stack_base_and_size();
const pthread_t pthread_id = ::pthread_self();
const tid_t kernel_thread_id = ::thread_self();
LogTarget(Info, os, thread) lt;
if (lt.is_enabled()) {
address low_address = thread->stack_end();
address high_address = thread->stack_base();
lt.print("Thread is alive (tid: " UINTX_FORMAT ", kernel thread id: " UINTX_FORMAT
", stack [" PTR_FORMAT " - " PTR_FORMAT " (" SIZE_FORMAT "k using %uk pages)).",
os::current_thread_id(), (uintx) kernel_thread_id, low_address, high_address,
(high_address - low_address) / K, os::Aix::query_pagesize(low_address) / K);
}
// Normally, pthread stacks on AIX live in the data segment (are allocated with malloc()
// by the pthread library). In rare cases, this may not be the case, e.g. when third-party
// tools hook pthread_create(). In this case, we may run into problems establishing
// guard pages on those stacks, because the stacks may reside in memory which is not
// protectable (shmated).
if (thread->stack_base() > ::sbrk(0)) {
log_warning(os, thread)("Thread stack not in data segment.");
}
// Try to randomize the cache line index of hot stack frames.
// This helps when threads of the same stack traces evict each other's
// cache lines. The threads can be either from the same JVM instance, or
// from different JVM instances. The benefit is especially true for
// processors with hyperthreading technology.
static int counter = 0;
int pid = os::current_process_id();
alloca(((pid ^ counter++) & 7) * 128);
thread->initialize_thread_current();
OSThread* osthread = thread->osthread();
// Thread_id is pthread id.
osthread->set_thread_id(pthread_id);
// .. but keep kernel thread id too for diagnostics
osthread->set_kernel_thread_id(kernel_thread_id);
// Initialize signal mask for this thread.
os::Aix::hotspot_sigmask(thread);
// Initialize floating point control register.
os::Aix::init_thread_fpu_state();
assert(osthread->get_state() == RUNNABLE, "invalid os thread state");
// Call one more level start routine.
thread->call_run();
// Note: at this point the thread object may already have deleted itself.
// Prevent dereferencing it from here on out.
thread = NULL;
log_info(os, thread)("Thread finished (tid: " UINTX_FORMAT ", kernel thread id: " UINTX_FORMAT ").",
os::current_thread_id(), (uintx) kernel_thread_id);
return 0;
}
bool os::create_thread(Thread* thread, ThreadType thr_type,
size_t req_stack_size) {
assert(thread->osthread() == NULL, "caller responsible");
// Allocate the OSThread object.
OSThread* osthread = new OSThread(NULL, NULL);
if (osthread == NULL) {
return false;
}
// Set the correct thread state.
osthread->set_thread_type(thr_type);
// Initial state is ALLOCATED but not INITIALIZED
osthread->set_state(ALLOCATED);
thread->set_osthread(osthread);
// Init thread attributes.
pthread_attr_t attr;
pthread_attr_init(&attr);
guarantee(pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED) == 0, "???");
// Make sure we run in 1:1 kernel-user-thread mode.
if (os::Aix::on_aix()) {
guarantee(pthread_attr_setscope(&attr, PTHREAD_SCOPE_SYSTEM) == 0, "???");
guarantee(pthread_attr_setinheritsched(&attr, PTHREAD_EXPLICIT_SCHED) == 0, "???");
}
// Start in suspended state, and in os::thread_start, wake the thread up.
guarantee(pthread_attr_setsuspendstate_np(&attr, PTHREAD_CREATE_SUSPENDED_NP) == 0, "???");
// Calculate stack size if it's not specified by caller.
size_t stack_size = os::Posix::get_initial_stack_size(thr_type, req_stack_size);
// JDK-8187028: It was observed that on some configurations (4K backed thread stacks)
// the real thread stack size may be smaller than the requested stack size, by as much as 64K.
// This very much looks like a pthread lib error. As a workaround, increase the stack size
// by 64K for small thread stacks (arbitrarily choosen to be < 4MB)
if (stack_size < 4096 * K) {
stack_size += 64 * K;
}
// On Aix, pthread_attr_setstacksize fails with huge values and leaves the
// thread size in attr unchanged. If this is the minimal stack size as set
// by pthread_attr_init this leads to crashes after thread creation. E.g. the
// guard pages might not fit on the tiny stack created.
int ret = pthread_attr_setstacksize(&attr, stack_size);
if (ret != 0) {
log_warning(os, thread)("The %sthread stack size specified is invalid: " SIZE_FORMAT "k",
(thr_type == compiler_thread) ? "compiler " : ((thr_type == java_thread) ? "" : "VM "),
stack_size / K);
thread->set_osthread(NULL);
delete osthread;
return false;
}
// Save some cycles and a page by disabling OS guard pages where we have our own
// VM guard pages (in java threads). For other threads, keep system default guard
// pages in place.
if (thr_type == java_thread || thr_type == compiler_thread) {
ret = pthread_attr_setguardsize(&attr, 0);
}
pthread_t tid = 0;
if (ret == 0) {
ret = pthread_create(&tid, &attr, (void* (*)(void*)) thread_native_entry, thread);
}
if (ret == 0) {
char buf[64];
log_info(os, thread)("Thread started (pthread id: " UINTX_FORMAT ", attributes: %s). ",
(uintx) tid, os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
} else {
char buf[64];
log_warning(os, thread)("Failed to start thread - pthread_create failed (%d=%s) for attributes: %s.",
ret, os::errno_name(ret), os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
// Log some OS information which might explain why creating the thread failed.
log_info(os, thread)("Number of threads approx. running in the VM: %d", Threads::number_of_threads());
LogStream st(Log(os, thread)::info());
os::Posix::print_rlimit_info(&st);
os::print_memory_info(&st);
}
pthread_attr_destroy(&attr);
if (ret != 0) {
// Need to clean up stuff we've allocated so far.
thread->set_osthread(NULL);
delete osthread;
return false;
}
// OSThread::thread_id is the pthread id.
osthread->set_thread_id(tid);
return true;
}
/////////////////////////////////////////////////////////////////////////////
// attach existing thread
// bootstrap the main thread
bool os::create_main_thread(JavaThread* thread) {
assert(os::Aix::_main_thread == pthread_self(), "should be called inside main thread");
return create_attached_thread(thread);
}
bool os::create_attached_thread(JavaThread* thread) {
#ifdef ASSERT
thread->verify_not_published();
#endif
// Allocate the OSThread object
OSThread* osthread = new OSThread(NULL, NULL);
if (osthread == NULL) {
return false;
}
const pthread_t pthread_id = ::pthread_self();
const tid_t kernel_thread_id = ::thread_self();
// OSThread::thread_id is the pthread id.
osthread->set_thread_id(pthread_id);
// .. but keep kernel thread id too for diagnostics
osthread->set_kernel_thread_id(kernel_thread_id);
// initialize floating point control register
os::Aix::init_thread_fpu_state();
// Initial thread state is RUNNABLE
osthread->set_state(RUNNABLE);
thread->set_osthread(osthread);
if (UseNUMA) {
int lgrp_id = os::numa_get_group_id();
if (lgrp_id != -1) {
thread->set_lgrp_id(lgrp_id);
}
}
// initialize signal mask for this thread
// and save the caller's signal mask
os::Aix::hotspot_sigmask(thread);
log_info(os, thread)("Thread attached (tid: " UINTX_FORMAT ", kernel thread id: " UINTX_FORMAT ").",
os::current_thread_id(), (uintx) kernel_thread_id);
return true;
}
void os::pd_start_thread(Thread* thread) {
int status = pthread_continue_np(thread->osthread()->pthread_id());
assert(status == 0, "thr_continue failed");
}
// Free OS resources related to the OSThread
void os::free_thread(OSThread* osthread) {
assert(osthread != NULL, "osthread not set");
// We are told to free resources of the argument thread,
// but we can only really operate on the current thread.
assert(Thread::current()->osthread() == osthread,
"os::free_thread but not current thread");
// Restore caller's signal mask
sigset_t sigmask = osthread->caller_sigmask();
pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
delete osthread;
}
////////////////////////////////////////////////////////////////////////////////
// time support
// Time since start-up in seconds to a fine granularity.
// Used by VMSelfDestructTimer and the MemProfiler.
double os::elapsedTime() {
return ((double)os::elapsed_counter()) / os::elapsed_frequency(); // nanosecond resolution
}
jlong os::elapsed_counter() {
return javaTimeNanos() - initial_time_count;
}
jlong os::elapsed_frequency() {
return NANOSECS_PER_SEC; // nanosecond resolution
}
bool os::supports_vtime() { return true; }
double os::elapsedVTime() {
struct rusage usage;
int retval = getrusage(RUSAGE_THREAD, &usage);
if (retval == 0) {
return usage.ru_utime.tv_sec + usage.ru_stime.tv_sec + (usage.ru_utime.tv_usec + usage.ru_stime.tv_usec) / (1000.0 * 1000);
} else {
// better than nothing, but not much
return elapsedTime();
}
}
jlong os::javaTimeMillis() {
timeval time;
int status = gettimeofday(&time, NULL);
assert(status != -1, "aix error at gettimeofday()");
return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
}
void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) {
timeval time;
int status = gettimeofday(&time, NULL);
assert(status != -1, "aix error at gettimeofday()");
seconds = jlong(time.tv_sec);
nanos = jlong(time.tv_usec) * 1000;
}
// We use mread_real_time here.
// On AIX: If the CPU has a time register, the result will be RTC_POWER and
// it has to be converted to real time. AIX documentations suggests to do
// this unconditionally, so we do it.
//
// See: https://www.ibm.com/support/knowledgecenter/ssw_aix_61/com.ibm.aix.basetrf2/read_real_time.htm
//
// On PASE: mread_real_time will always return RTC_POWER_PC data, so no
// conversion is necessary. However, mread_real_time will not return
// monotonic results but merely matches read_real_time. So we need a tweak
// to ensure monotonic results.
//
// For PASE no public documentation exists, just word by IBM
jlong os::javaTimeNanos() {
timebasestruct_t time;
int rc = mread_real_time(&time, TIMEBASE_SZ);
if (os::Aix::on_pase()) {
assert(rc == RTC_POWER, "expected time format RTC_POWER from mread_real_time in PASE");
jlong now = jlong(time.tb_high) * NANOSECS_PER_SEC + jlong(time.tb_low);
jlong prev = max_real_time;
if (now <= prev) {
return prev; // same or retrograde time;
}
jlong obsv = Atomic::cmpxchg(&max_real_time, prev, now);
assert(obsv >= prev, "invariant"); // Monotonicity
// If the CAS succeeded then we're done and return "now".
// If the CAS failed and the observed value "obsv" is >= now then
// we should return "obsv". If the CAS failed and now > obsv > prv then
// some other thread raced this thread and installed a new value, in which case
// we could either (a) retry the entire operation, (b) retry trying to install now
// or (c) just return obsv. We use (c). No loop is required although in some cases
// we might discard a higher "now" value in deference to a slightly lower but freshly
// installed obsv value. That's entirely benign -- it admits no new orderings compared
// to (a) or (b) -- and greatly reduces coherence traffic.
// We might also condition (c) on the magnitude of the delta between obsv and now.
// Avoiding excessive CAS operations to hot RW locations is critical.
// See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate
return (prev == obsv) ? now : obsv;
} else {
if (rc != RTC_POWER) {
rc = time_base_to_time(&time, TIMEBASE_SZ);
assert(rc != -1, "error calling time_base_to_time()");
}
return jlong(time.tb_high) * NANOSECS_PER_SEC + jlong(time.tb_low);
}
}
void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
info_ptr->max_value = ALL_64_BITS;
// mread_real_time() is monotonic (see 'os::javaTimeNanos()')
info_ptr->may_skip_backward = false;
info_ptr->may_skip_forward = false;
info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
}
// Return the real, user, and system times in seconds from an
// arbitrary fixed point in the past.
bool os::getTimesSecs(double* process_real_time,
double* process_user_time,
double* process_system_time) {
struct tms ticks;
clock_t real_ticks = times(&ticks);
if (real_ticks == (clock_t) (-1)) {
return false;
} else {
double ticks_per_second = (double) clock_tics_per_sec;
*process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
*process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
*process_real_time = ((double) real_ticks) / ticks_per_second;
return true;
}
}
char * os::local_time_string(char *buf, size_t buflen) {
struct tm t;
time_t long_time;
time(&long_time);
localtime_r(&long_time, &t);
jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
t.tm_hour, t.tm_min, t.tm_sec);
return buf;
}
struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
return localtime_r(clock, res);
}
////////////////////////////////////////////////////////////////////////////////
// runtime exit support
// Note: os::shutdown() might be called very early during initialization, or
// called from signal handler. Before adding something to os::shutdown(), make
// sure it is async-safe and can handle partially initialized VM.
void os::shutdown() {
// allow PerfMemory to attempt cleanup of any persistent resources
perfMemory_exit();
// needs to remove object in file system
AttachListener::abort();
// flush buffered output, finish log files
ostream_abort();
// Check for abort hook
abort_hook_t abort_hook = Arguments::abort_hook();
if (abort_hook != NULL) {
abort_hook();
}
}
// Note: os::abort() might be called very early during initialization, or
// called from signal handler. Before adding something to os::abort(), make
// sure it is async-safe and can handle partially initialized VM.
void os::abort(bool dump_core, void* siginfo, const void* context) {
os::shutdown();
if (dump_core) {
#ifndef PRODUCT
fdStream out(defaultStream::output_fd());
out.print_raw("Current thread is ");
char buf[16];
jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
out.print_raw_cr(buf);
out.print_raw_cr("Dumping core ...");
#endif
::abort(); // dump core
}
::exit(1);
}
// Die immediately, no exit hook, no abort hook, no cleanup.
// Dump a core file, if possible, for debugging.
void os::die() {
if (TestUnresponsiveErrorHandler && !CreateCoredumpOnCrash) {
// For TimeoutInErrorHandlingTest.java, we just kill the VM
// and don't take the time to generate a core file.
os::signal_raise(SIGKILL);
} else {
::abort();
}
}
intx os::current_thread_id() {
return (intx)pthread_self();
}
int os::current_process_id() {
return getpid();
}
// DLL functions
const char* os::dll_file_extension() { return ".so"; }
// This must be hard coded because it's the system's temporary
// directory not the java application's temp directory, ala java.io.tmpdir.
const char* os::get_temp_directory() { return "/tmp"; }
// Check if addr is inside libjvm.so.
bool os::address_is_in_vm(address addr) {
// Input could be a real pc or a function pointer literal. The latter
// would be a function descriptor residing in the data segment of a module.
loaded_module_t lm;
if (LoadedLibraries::find_for_text_address(addr, &lm) != NULL) {
return lm.is_in_vm;
} else if (LoadedLibraries::find_for_data_address(addr, &lm) != NULL) {
return lm.is_in_vm;
} else {
return false;
}
}
// Resolve an AIX function descriptor literal to a code pointer.
// If the input is a valid code pointer to a text segment of a loaded module,
// it is returned unchanged.
// If the input is a valid AIX function descriptor, it is resolved to the
// code entry point.
// If the input is neither a valid function descriptor nor a valid code pointer,
// NULL is returned.
static address resolve_function_descriptor_to_code_pointer(address p) {
if (LoadedLibraries::find_for_text_address(p, NULL) != NULL) {
// It is a real code pointer.
return p;
} else if (LoadedLibraries::find_for_data_address(p, NULL) != NULL) {
// Pointer to data segment, potential function descriptor.
address code_entry = (address)(((FunctionDescriptor*)p)->entry());
if (LoadedLibraries::find_for_text_address(code_entry, NULL) != NULL) {
// It is a function descriptor.
return code_entry;
}
}
return NULL;
}
bool os::dll_address_to_function_name(address addr, char *buf,
int buflen, int *offset,
bool demangle) {
if (offset) {
*offset = -1;
}
// Buf is not optional, but offset is optional.
assert(buf != NULL, "sanity check");
buf[0] = '\0';
// Resolve function ptr literals first.
addr = resolve_function_descriptor_to_code_pointer(addr);
if (!addr) {
return false;
}
return AixSymbols::get_function_name(addr, buf, buflen, offset, NULL, demangle);
}
bool os::dll_address_to_library_name(address addr, char* buf,
int buflen, int* offset) {
if (offset) {
*offset = -1;
}
// Buf is not optional, but offset is optional.
assert(buf != NULL, "sanity check");
buf[0] = '\0';
// Resolve function ptr literals first.
addr = resolve_function_descriptor_to_code_pointer(addr);
if (!addr) {
return false;
}
return AixSymbols::get_module_name(addr, buf, buflen);
}
// Loads .dll/.so and in case of error it checks if .dll/.so was built
// for the same architecture as Hotspot is running on.
void *os::dll_load(const char *filename, char *ebuf, int ebuflen) {
log_info(os)("attempting shared library load of %s", filename);
if (ebuf && ebuflen > 0) {
ebuf[0] = '\0';
ebuf[ebuflen - 1] = '\0';
}
if (!filename || strlen(filename) == 0) {
::strncpy(ebuf, "dll_load: empty filename specified", ebuflen - 1);
return NULL;
}
// RTLD_LAZY is currently not implemented. The dl is loaded immediately with all its dependants.
void * result= ::dlopen(filename, RTLD_LAZY);
if (result != NULL) {
Events::log(NULL, "Loaded shared library %s", filename);
// Reload dll cache. Don't do this in signal handling.
LoadedLibraries::reload();
log_info(os)("shared library load of %s was successful", filename);
return result;
} else {
// error analysis when dlopen fails
const char* error_report = ::dlerror();
if (error_report == NULL) {
error_report = "dlerror returned no error description";
}
if (ebuf != NULL && ebuflen > 0) {
snprintf(ebuf, ebuflen - 1, "%s, LIBPATH=%s, LD_LIBRARY_PATH=%s : %s",
filename, ::getenv("LIBPATH"), ::getenv("LD_LIBRARY_PATH"), error_report);
}
Events::log(NULL, "Loading shared library %s failed, %s", filename, error_report);
log_info(os)("shared library load of %s failed, %s", filename, error_report);
}
return NULL;
}
void* os::dll_lookup(void* handle, const char* name) {
void* res = dlsym(handle, name);
return res;
}
void* os::get_default_process_handle() {
return (void*)::dlopen(NULL, RTLD_LAZY);
}
void os::print_dll_info(outputStream *st) {
st->print_cr("Dynamic libraries:");
LoadedLibraries::print(st);
}
void os::get_summary_os_info(char* buf, size_t buflen) {
// There might be something more readable than uname results for AIX.
struct utsname name;
uname(&name);
snprintf(buf, buflen, "%s %s", name.release, name.version);
}
int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) {
// Not yet implemented.
return 0;
}
void os::print_os_info_brief(outputStream* st) {
uint32_t ver = os::Aix::os_version();
st->print_cr("AIX kernel version %u.%u.%u.%u",
(ver >> 24) & 0xFF, (ver >> 16) & 0xFF, (ver >> 8) & 0xFF, ver & 0xFF);
os::Posix::print_uname_info(st);
// Linux uses print_libversion_info(st); here.
}
void os::print_os_info(outputStream* st) {
st->print("OS:");
os::Posix::print_uname_info(st);
uint32_t ver = os::Aix::os_version();
st->print_cr("AIX kernel version %u.%u.%u.%u",
(ver >> 24) & 0xFF, (ver >> 16) & 0xFF, (ver >> 8) & 0xFF, ver & 0xFF);
os::Posix::print_uptime_info(st);
os::Posix::print_rlimit_info(st);
os::Posix::print_load_average(st);
// _SC_THREAD_THREADS_MAX is the maximum number of threads within a process.
long tmax = sysconf(_SC_THREAD_THREADS_MAX);
st->print_cr("maximum #threads within a process:%ld", tmax);
// print wpar info
libperfstat::wparinfo_t wi;
if (libperfstat::get_wparinfo(&wi)) {
st->print_cr("wpar info");
st->print_cr("name: %s", wi.name);
st->print_cr("id: %d", wi.wpar_id);
st->print_cr("type: %s", (wi.app_wpar ? "application" : "system"));
}
VM_Version::print_platform_virtualization_info(st);
}
void os::print_memory_info(outputStream* st) {
st->print_cr("Memory:");
st->print_cr(" Base page size (sysconf _SC_PAGESIZE): %s",
describe_pagesize(g_multipage_support.pagesize));
st->print_cr(" Data page size (C-Heap, bss, etc): %s",
describe_pagesize(g_multipage_support.datapsize));
st->print_cr(" Text page size: %s",
describe_pagesize(g_multipage_support.textpsize));
st->print_cr(" Thread stack page size (pthread): %s",
describe_pagesize(g_multipage_support.pthr_stack_pagesize));
st->print_cr(" Default shared memory page size: %s",
describe_pagesize(g_multipage_support.shmpsize));
st->print_cr(" Can use 64K pages dynamically with shared memory: %s",
(g_multipage_support.can_use_64K_pages ? "yes" :"no"));
st->print_cr(" Can use 16M pages dynamically with shared memory: %s",
(g_multipage_support.can_use_16M_pages ? "yes" :"no"));
st->print_cr(" Multipage error: %d",
g_multipage_support.error);
st->cr();
st->print_cr(" os::vm_page_size: %s", describe_pagesize(os::vm_page_size()));
// print out LDR_CNTRL because it affects the default page sizes
const char* const ldr_cntrl = ::getenv("LDR_CNTRL");
st->print_cr(" LDR_CNTRL=%s.", ldr_cntrl ? ldr_cntrl : "<unset>");
// Print out EXTSHM because it is an unsupported setting.
const char* const extshm = ::getenv("EXTSHM");
st->print_cr(" EXTSHM=%s.", extshm ? extshm : "<unset>");
if ( (strcmp(extshm, "on") == 0) || (strcmp(extshm, "ON") == 0) ) {
st->print_cr(" *** Unsupported! Please remove EXTSHM from your environment! ***");
}
// Print out AIXTHREAD_GUARDPAGES because it affects the size of pthread stacks.
const char* const aixthread_guardpages = ::getenv("AIXTHREAD_GUARDPAGES");
st->print_cr(" AIXTHREAD_GUARDPAGES=%s.",
aixthread_guardpages ? aixthread_guardpages : "<unset>");
st->cr();
os::Aix::meminfo_t mi;
if (os::Aix::get_meminfo(&mi)) {
if (os::Aix::on_aix()) {
st->print_cr("physical total : " SIZE_FORMAT, mi.real_total);
st->print_cr("physical free : " SIZE_FORMAT, mi.real_free);
st->print_cr("swap total : " SIZE_FORMAT, mi.pgsp_total);
st->print_cr("swap free : " SIZE_FORMAT, mi.pgsp_free);
} else {
// PASE - Numbers are result of QWCRSSTS; they mean:
// real_total: Sum of all system pools
// real_free: always 0
// pgsp_total: we take the size of the system ASP
// pgsp_free: size of system ASP times percentage of system ASP unused
st->print_cr("physical total : " SIZE_FORMAT, mi.real_total);
st->print_cr("system asp total : " SIZE_FORMAT, mi.pgsp_total);
st->print_cr("%% system asp used : %.2f",
mi.pgsp_total ? (100.0f * (mi.pgsp_total - mi.pgsp_free) / mi.pgsp_total) : -1.0f);
}
}
st->cr();
// Print program break.
st->print_cr("Program break at VM startup: " PTR_FORMAT ".", p2i(g_brk_at_startup));
address brk_now = (address)::sbrk(0);
if (brk_now != (address)-1) {
st->print_cr("Program break now : " PTR_FORMAT " (distance: " SIZE_FORMAT "k).",
p2i(brk_now), (size_t)((brk_now - g_brk_at_startup) / K));
}
st->print_cr("MaxExpectedDataSegmentSize : " SIZE_FORMAT "k.", MaxExpectedDataSegmentSize / K);
st->cr();
// Print segments allocated with os::reserve_memory.
st->print_cr("internal virtual memory regions used by vm:");
vmembk_print_on(st);
}
// Get a string for the cpuinfo that is a summary of the cpu type
void os::get_summary_cpu_info(char* buf, size_t buflen) {
// read _system_configuration.version
switch (_system_configuration.version) {
case PV_9:
strncpy(buf, "Power PC 9", buflen);
break;
case PV_8:
strncpy(buf, "Power PC 8", buflen);
break;
case PV_7:
strncpy(buf, "Power PC 7", buflen);
break;
case PV_6_1:
strncpy(buf, "Power PC 6 DD1.x", buflen);
break;
case PV_6:
strncpy(buf, "Power PC 6", buflen);
break;
case PV_5:
strncpy(buf, "Power PC 5", buflen);
break;
case PV_5_2:
strncpy(buf, "Power PC 5_2", buflen);
break;
case PV_5_3:
strncpy(buf, "Power PC 5_3", buflen);
break;
case PV_5_Compat:
strncpy(buf, "PV_5_Compat", buflen);
break;
case PV_6_Compat:
strncpy(buf, "PV_6_Compat", buflen);
break;
case PV_7_Compat:
strncpy(buf, "PV_7_Compat", buflen);
break;
case PV_8_Compat:
strncpy(buf, "PV_8_Compat", buflen);
break;
case PV_9_Compat:
strncpy(buf, "PV_9_Compat", buflen);
break;
default:
strncpy(buf, "unknown", buflen);
}
}
void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) {
// Nothing to do beyond of what os::print_cpu_info() does.
}
static void print_signal_handler(outputStream* st, int sig,
char* buf, size_t buflen);
void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
st->print_cr("Signal Handlers:");
print_signal_handler(st, SIGSEGV, buf, buflen);
print_signal_handler(st, SIGBUS , buf, buflen);
print_signal_handler(st, SIGFPE , buf, buflen);
print_signal_handler(st, SIGPIPE, buf, buflen);
print_signal_handler(st, SIGXFSZ, buf, buflen);
print_signal_handler(st, SIGILL , buf, buflen);
print_signal_handler(st, SR_signum, buf, buflen);
print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
print_signal_handler(st, SIGTRAP, buf, buflen);
// We also want to know if someone else adds a SIGDANGER handler because
// that will interfere with OOM killling.
print_signal_handler(st, SIGDANGER, buf, buflen);
}
static char saved_jvm_path[MAXPATHLEN] = {0};
// Find the full path to the current module, libjvm.so.
void os::jvm_path(char *buf, jint buflen) {
// Error checking.
if (buflen < MAXPATHLEN) {
assert(false, "must use a large-enough buffer");
buf[0] = '\0';
return;
}
// Lazy resolve the path to current module.
if (saved_jvm_path[0] != 0) {
strcpy(buf, saved_jvm_path);
return;
}
Dl_info dlinfo;
int ret = dladdr(CAST_FROM_FN_PTR(void *, os::jvm_path), &dlinfo);
assert(ret != 0, "cannot locate libjvm");
char* rp = os::Posix::realpath((char *)dlinfo.dli_fname, buf, buflen);
assert(rp != NULL, "error in realpath(): maybe the 'path' argument is too long?");
if (Arguments::sun_java_launcher_is_altjvm()) {
// Support for the java launcher's '-XXaltjvm=<path>' option. Typical
// value for buf is "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.so".
// If "/jre/lib/" appears at the right place in the string, then
// assume we are installed in a JDK and we're done. Otherwise, check
// for a JAVA_HOME environment variable and fix up the path so it
// looks like libjvm.so is installed there (append a fake suffix
// hotspot/libjvm.so).
const char *p = buf + strlen(buf) - 1;
for (int count = 0; p > buf && count < 4; ++count) {
for (--p; p > buf && *p != '/'; --p)
/* empty */ ;
}
if (strncmp(p, "/jre/lib/", 9) != 0) {
// Look for JAVA_HOME in the environment.
char* java_home_var = ::getenv("JAVA_HOME");
if (java_home_var != NULL && java_home_var[0] != 0) {
char* jrelib_p;
int len;
// Check the current module name "libjvm.so".
p = strrchr(buf, '/');
if (p == NULL) {
return;
}
assert(strstr(p, "/libjvm") == p, "invalid library name");
rp = os::Posix::realpath(java_home_var, buf, buflen);
if (rp == NULL) {
return;
}
// determine if this is a legacy image or modules image
// modules image doesn't have "jre" subdirectory
len = strlen(buf);
assert(len < buflen, "Ran out of buffer room");
jrelib_p = buf + len;
snprintf(jrelib_p, buflen-len, "/jre/lib");
if (0 != access(buf, F_OK)) {
snprintf(jrelib_p, buflen-len, "/lib");
}
if (0 == access(buf, F_OK)) {
// Use current module name "libjvm.so"
len = strlen(buf);
snprintf(buf + len, buflen-len, "/hotspot/libjvm.so");
} else {
// Go back to path of .so
rp = os::Posix::realpath((char *)dlinfo.dli_fname, buf, buflen);
if (rp == NULL) {
return;
}
}
}
}
}
strncpy(saved_jvm_path, buf, sizeof(saved_jvm_path));
saved_jvm_path[sizeof(saved_jvm_path) - 1] = '\0';
}
void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
// no prefix required, not even "_"
}
void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
// no suffix required
}
////////////////////////////////////////////////////////////////////////////////
// sun.misc.Signal support
static void
UserHandler(int sig, void *siginfo, void *context) {
// Ctrl-C is pressed during error reporting, likely because the error
// handler fails to abort. Let VM die immediately.
if (sig == SIGINT && VMError::is_error_reported()) {
os::die();
}
os::signal_notify(sig);
}
void* os::user_handler() {
return CAST_FROM_FN_PTR(void*, UserHandler);
}
extern "C" {
typedef void (*sa_handler_t)(int);
typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
}
void* os::signal(int signal_number, void* handler) {
struct sigaction sigAct, oldSigAct;
sigfillset(&(sigAct.sa_mask));
// Do not block out synchronous signals in the signal handler.
// Blocking synchronous signals only makes sense if you can really
// be sure that those signals won't happen during signal handling,
// when the blocking applies. Normal signal handlers are lean and
// do not cause signals. But our signal handlers tend to be "risky"
// - secondary SIGSEGV, SIGILL, SIGBUS' may and do happen.
// On AIX, PASE there was a case where a SIGSEGV happened, followed
// by a SIGILL, which was blocked due to the signal mask. The process
// just hung forever. Better to crash from a secondary signal than to hang.
sigdelset(&(sigAct.sa_mask), SIGSEGV);
sigdelset(&(sigAct.sa_mask), SIGBUS);
sigdelset(&(sigAct.sa_mask), SIGILL);
sigdelset(&(sigAct.sa_mask), SIGFPE);
sigdelset(&(sigAct.sa_mask), SIGTRAP);
sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
if (sigaction(signal_number, &sigAct, &oldSigAct)) {
// -1 means registration failed
return (void *)-1;
}
return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
}
void os::signal_raise(int signal_number) {
::raise(signal_number);
}
//
// The following code is moved from os.cpp for making this
// code platform specific, which it is by its very nature.
//
// Will be modified when max signal is changed to be dynamic
int os::sigexitnum_pd() {
return NSIG;
}
// a counter for each possible signal value
static volatile jint pending_signals[NSIG+1] = { 0 };
// Wrapper functions for: sem_init(), sem_post(), sem_wait()
// On AIX, we use sem_init(), sem_post(), sem_wait()
// On Pase, we need to use msem_lock() and msem_unlock(), because Posix Semaphores
// do not seem to work at all on PASE (unimplemented, will cause SIGILL).
// Note that just using msem_.. APIs for both PASE and AIX is not an option either, as
// on AIX, msem_..() calls are suspected of causing problems.
static sem_t sig_sem;
static msemaphore* p_sig_msem = 0;
static void local_sem_init() {
if (os::Aix::on_aix()) {
int rc = ::sem_init(&sig_sem, 0, 0);
guarantee(rc != -1, "sem_init failed");
} else {
// Memory semaphores must live in shared mem.
guarantee0(p_sig_msem == NULL);
p_sig_msem = (msemaphore*)os::reserve_memory(sizeof(msemaphore), NULL);
guarantee(p_sig_msem, "Cannot allocate memory for memory semaphore");
guarantee(::msem_init(p_sig_msem, 0) == p_sig_msem, "msem_init failed");
}
}
static void local_sem_post() {
static bool warn_only_once = false;
if (os::Aix::on_aix()) {
int rc = ::sem_post(&sig_sem);
if (rc == -1 && !warn_only_once) {
trcVerbose("sem_post failed (errno = %d, %s)", errno, os::errno_name(errno));
warn_only_once = true;
}
} else {
guarantee0(p_sig_msem != NULL);
int rc = ::msem_unlock(p_sig_msem, 0);
if (rc == -1 && !warn_only_once) {
trcVerbose("msem_unlock failed (errno = %d, %s)", errno, os::errno_name(errno));
warn_only_once = true;
}
}
}
static void local_sem_wait() {
static bool warn_only_once = false;
if (os::Aix::on_aix()) {
int rc = ::sem_wait(&sig_sem);
if (rc == -1 && !warn_only_once) {
trcVerbose("sem_wait failed (errno = %d, %s)", errno, os::errno_name(errno));
warn_only_once = true;
}
} else {
guarantee0(p_sig_msem != NULL); // must init before use
int rc = ::msem_lock(p_sig_msem, 0);
if (rc == -1 && !warn_only_once) {
trcVerbose("msem_lock failed (errno = %d, %s)", errno, os::errno_name(errno));
warn_only_once = true;
}
}
}
static void jdk_misc_signal_init() {
// Initialize signal structures
::memset((void*)pending_signals, 0, sizeof(pending_signals));
// Initialize signal semaphore
local_sem_init();
}
void os::signal_notify(int sig) {
Atomic::inc(&pending_signals[sig]);
local_sem_post();
}
static int check_pending_signals() {
for (;;) {
for (int i = 0; i < NSIG + 1; i++) {
jint n = pending_signals[i];
if (n > 0 && n == Atomic::cmpxchg(&pending_signals[i], n, n - 1)) {
return i;
}
}
JavaThread *thread = JavaThread::current();
ThreadBlockInVM tbivm(thread);
bool threadIsSuspended;
do {
thread->set_suspend_equivalent();
// cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
local_sem_wait();
// were we externally suspended while we were waiting?
threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
if (threadIsSuspended) {
//
// The semaphore has been incremented, but while we were waiting
// another thread suspended us. We don't want to continue running
// while suspended because that would surprise the thread that
// suspended us.
//
local_sem_post();
thread->java_suspend_self();
}
} while (threadIsSuspended);
}
}
int os::signal_wait() {
return check_pending_signals();
}
////////////////////////////////////////////////////////////////////////////////
// Virtual Memory
// We need to keep small simple bookkeeping for os::reserve_memory and friends.
#define VMEM_MAPPED 1
#define VMEM_SHMATED 2
struct vmembk_t {
int type; // 1 - mmap, 2 - shmat
char* addr;
size_t size; // Real size, may be larger than usersize.
size_t pagesize; // page size of area
vmembk_t* next;
bool contains_addr(char* p) const {
return p >= addr && p < (addr + size);
}
bool contains_range(char* p, size_t s) const {
return contains_addr(p) && contains_addr(p + s - 1);
}
void print_on(outputStream* os) const {
os->print("[" PTR_FORMAT " - " PTR_FORMAT "] (" UINTX_FORMAT
" bytes, %d %s pages), %s",
addr, addr + size - 1, size, size / pagesize, describe_pagesize(pagesize),
(type == VMEM_SHMATED ? "shmat" : "mmap")
);
}
// Check that range is a sub range of memory block (or equal to memory block);
// also check that range is fully page aligned to the page size if the block.
void assert_is_valid_subrange(char* p, size_t s) const {
if (!contains_range(p, s)) {
trcVerbose("[" PTR_FORMAT " - " PTR_FORMAT "] is not a sub "
"range of [" PTR_FORMAT " - " PTR_FORMAT "].",
p2i(p), p2i(p + s), p2i(addr), p2i(addr + size));
guarantee0(false);
}
if (!is_aligned_to(p, pagesize) || !is_aligned_to(p + s, pagesize)) {
trcVerbose("range [" PTR_FORMAT " - " PTR_FORMAT "] is not"
" aligned to pagesize (%lu)", p2i(p), p2i(p + s), (unsigned long) pagesize);
guarantee0(false);
}
}
};
static struct {
vmembk_t* first;
MiscUtils::CritSect cs;
} vmem;
static void vmembk_add(char* addr, size_t size, size_t pagesize, int type) {
vmembk_t* p = (vmembk_t*) ::malloc(sizeof(vmembk_t));
assert0(p);
if (p) {
MiscUtils::AutoCritSect lck(&vmem.cs);
p->addr = addr; p->size = size;
p->pagesize = pagesize;
p->type = type;
p->next = vmem.first;
vmem.first = p;
}
}
static vmembk_t* vmembk_find(char* addr) {
MiscUtils::AutoCritSect lck(&vmem.cs);
for (vmembk_t* p = vmem.first; p; p = p->next) {
if (p->addr <= addr && (p->addr + p->size) > addr) {
return p;
}
}
return NULL;
}
static void vmembk_remove(vmembk_t* p0) {
MiscUtils::AutoCritSect lck(&vmem.cs);
assert0(p0);
assert0(vmem.first); // List should not be empty.
for (vmembk_t** pp = &(vmem.first); *pp; pp = &((*pp)->next)) {
if (*pp == p0) {
*pp = p0->next;
::free(p0);
return;
}
}
assert0(false); // Not found?
}
static void vmembk_print_on(outputStream* os) {
MiscUtils::AutoCritSect lck(&vmem.cs);
for (vmembk_t* vmi = vmem.first; vmi; vmi = vmi->next) {
vmi->print_on(os);
os->cr();
}
}
// Reserve and attach a section of System V memory.
// If <requested_addr> is not NULL, function will attempt to attach the memory at the given
// address. Failing that, it will attach the memory anywhere.
// If <requested_addr> is NULL, function will attach the memory anywhere.
//
// <alignment_hint> is being ignored by this function. It is very probable however that the
// alignment requirements are met anyway, because shmat() attaches at 256M boundaries.
// Should this be not enogh, we can put more work into it.
static char* reserve_shmated_memory (
size_t bytes,
char* requested_addr,
size_t alignment_hint) {
trcVerbose("reserve_shmated_memory " UINTX_FORMAT " bytes, wishaddress "
PTR_FORMAT ", alignment_hint " UINTX_FORMAT "...",
bytes, p2i(requested_addr), alignment_hint);
// Either give me wish address or wish alignment but not both.
assert0(!(requested_addr != NULL && alignment_hint != 0));
// We must prevent anyone from attaching too close to the
// BRK because that may cause malloc OOM.
if (requested_addr != NULL && is_close_to_brk((address)requested_addr)) {
trcVerbose("Wish address " PTR_FORMAT " is too close to the BRK segment. "
"Will attach anywhere.", p2i(requested_addr));
// Act like the OS refused to attach there.
requested_addr = NULL;
}
// For old AS/400's (V5R4 and older) we should not even be here - System V shared memory is not
// really supported (max size 4GB), so reserve_mmapped_memory should have been used instead.
if (os::Aix::on_pase_V5R4_or_older()) {
ShouldNotReachHere();
}
// Align size of shm up to 64K to avoid errors if we later try to change the page size.
const size_t size = align_up(bytes, 64*K);
// Reserve the shared segment.
int shmid = shmget(IPC_PRIVATE, size, IPC_CREAT | S_IRUSR | S_IWUSR);
if (shmid == -1) {
trcVerbose("shmget(.., " UINTX_FORMAT ", ..) failed (errno: %d).", size, errno);
return NULL;
}
// Important note:
// It is very important that we, upon leaving this function, do not leave a shm segment alive.
// We must right after attaching it remove it from the system. System V shm segments are global and
// survive the process.
// So, from here on: Do not assert, do not return, until we have called shmctl(IPC_RMID) (A).
struct shmid_ds shmbuf;
memset(&shmbuf, 0, sizeof(shmbuf));
shmbuf.shm_pagesize = 64*K;
if (shmctl(shmid, SHM_PAGESIZE, &shmbuf) != 0) {
trcVerbose("Failed to set page size (need " UINTX_FORMAT " 64K pages) - shmctl failed with %d.",
size / (64*K), errno);
// I want to know if this ever happens.
assert(false, "failed to set page size for shmat");
}
// Now attach the shared segment.
// Note that I attach with SHM_RND - which means that the requested address is rounded down, if
// needed, to the next lowest segment boundary. Otherwise the attach would fail if the address
// were not a segment boundary.
char* const addr = (char*) shmat(shmid, requested_addr, SHM_RND);
const int errno_shmat = errno;
// (A) Right after shmat and before handing shmat errors delete the shm segment.
if (::shmctl(shmid, IPC_RMID, NULL) == -1) {
trcVerbose("shmctl(%u, IPC_RMID) failed (%d)\n", shmid, errno);
assert(false, "failed to remove shared memory segment!");
}
// Handle shmat error. If we failed to attach, just return.
if (addr == (char*)-1) {
trcVerbose("Failed to attach segment at " PTR_FORMAT " (%d).", p2i(requested_addr), errno_shmat);
return NULL;
}
// Just for info: query the real page size. In case setting the page size did not
// work (see above), the system may have given us something other then 4K (LDR_CNTRL).
const size_t real_pagesize = os::Aix::query_pagesize(addr);
if (real_pagesize != shmbuf.shm_pagesize) {
trcVerbose("pagesize is, surprisingly, " SIZE_FORMAT, real_pagesize);
}
if (addr) {
trcVerbose("shm-allocated " PTR_FORMAT " .. " PTR_FORMAT " (" UINTX_FORMAT " bytes, " UINTX_FORMAT " %s pages)",
p2i(addr), p2i(addr + size - 1), size, size/real_pagesize, describe_pagesize(real_pagesize));
} else {
if (requested_addr != NULL) {
trcVerbose("failed to shm-allocate " UINTX_FORMAT " bytes at with address " PTR_FORMAT ".", size, p2i(requested_addr));
} else {
trcVerbose("failed to shm-allocate " UINTX_FORMAT " bytes at any address.", size);
}
}
// book-keeping
vmembk_add(addr, size, real_pagesize, VMEM_SHMATED);
assert0(is_aligned_to(addr, os::vm_page_size()));
return addr;
}
static bool release_shmated_memory(char* addr, size_t size) {
trcVerbose("release_shmated_memory [" PTR_FORMAT " - " PTR_FORMAT "].",
p2i(addr), p2i(addr + size - 1));
bool rc = false;
// TODO: is there a way to verify shm size without doing bookkeeping?
if (::shmdt(addr) != 0) {
trcVerbose("error (%d).", errno);
} else {
trcVerbose("ok.");
rc = true;
}
return rc;
}
static bool uncommit_shmated_memory(char* addr, size_t size) {
trcVerbose("uncommit_shmated_memory [" PTR_FORMAT " - " PTR_FORMAT "].",
p2i(addr), p2i(addr + size - 1));
const bool rc = my_disclaim64(addr, size);
if (!rc) {
trcVerbose("my_disclaim64(" PTR_FORMAT ", " UINTX_FORMAT ") failed.\n", p2i(addr), size);
return false;
}
return true;
}
//////////////////////////////// mmap-based routines /////////////////////////////////
// Reserve memory via mmap.
// If <requested_addr> is given, an attempt is made to attach at the given address.
// Failing that, memory is allocated at any address.
// If <alignment_hint> is given and <requested_addr> is NULL, an attempt is made to
// allocate at an address aligned with the given alignment. Failing that, memory
// is aligned anywhere.
static char* reserve_mmaped_memory(size_t bytes, char* requested_addr, size_t alignment_hint) {
trcVerbose("reserve_mmaped_memory " UINTX_FORMAT " bytes, wishaddress " PTR_FORMAT ", "
"alignment_hint " UINTX_FORMAT "...",
bytes, p2i(requested_addr), alignment_hint);
// If a wish address is given, but not aligned to 4K page boundary, mmap will fail.
if (requested_addr && !is_aligned_to(requested_addr, os::vm_page_size()) != 0) {
trcVerbose("Wish address " PTR_FORMAT " not aligned to page boundary.", p2i(requested_addr));
return NULL;
}
// We must prevent anyone from attaching too close to the
// BRK because that may cause malloc OOM.
if (requested_addr != NULL && is_close_to_brk((address)requested_addr)) {
trcVerbose("Wish address " PTR_FORMAT " is too close to the BRK segment. "
"Will attach anywhere.", p2i(requested_addr));
// Act like the OS refused to attach there.
requested_addr = NULL;
}
// Specify one or the other but not both.
assert0(!(requested_addr != NULL && alignment_hint > 0));
// In 64K mode, we claim the global page size (os::vm_page_size())
// is 64K. This is one of the few points where that illusion may
// break, because mmap() will always return memory aligned to 4K. So
// we must ensure we only ever return memory aligned to 64k.
if (alignment_hint) {
alignment_hint = lcm(alignment_hint, os::vm_page_size());
} else {
alignment_hint = os::vm_page_size();
}
// Size shall always be a multiple of os::vm_page_size (esp. in 64K mode).
const size_t size = align_up(bytes, os::vm_page_size());
// alignment: Allocate memory large enough to include an aligned range of the right size and
// cut off the leading and trailing waste pages.
assert0(alignment_hint != 0 && is_aligned_to(alignment_hint, os::vm_page_size())); // see above
const size_t extra_size = size + alignment_hint;
// Note: MAP_SHARED (instead of MAP_PRIVATE) needed to be able to
// later use msync(MS_INVALIDATE) (see os::uncommit_memory).
int flags = MAP_ANONYMOUS | MAP_SHARED;
// MAP_FIXED is needed to enforce requested_addr - manpage is vague about what
// it means if wishaddress is given but MAP_FIXED is not set.
//
// Important! Behaviour differs depending on whether SPEC1170 mode is active or not.
// SPEC1170 mode active: behaviour like POSIX, MAP_FIXED will clobber existing mappings.
// SPEC1170 mode not active: behaviour, unlike POSIX, is that no existing mappings will
// get clobbered.
if (requested_addr != NULL) {
if (!os::Aix::xpg_sus_mode()) { // not SPEC1170 Behaviour
flags |= MAP_FIXED;
}
}
char* addr = (char*)::mmap(requested_addr, extra_size,
PROT_READ|PROT_WRITE|PROT_EXEC, flags, -1, 0);
if (addr == MAP_FAILED) {
trcVerbose("mmap(" PTR_FORMAT ", " UINTX_FORMAT ", ..) failed (%d)", p2i(requested_addr), size, errno);
return NULL;
}
// Handle alignment.
char* const addr_aligned = align_up(addr, alignment_hint);
const size_t waste_pre = addr_aligned - addr;
char* const addr_aligned_end = addr_aligned + size;
const size_t waste_post = extra_size - waste_pre - size;
if (waste_pre > 0) {
::munmap(addr, waste_pre);
}
if (waste_post > 0) {
::munmap(addr_aligned_end, waste_post);
}
addr = addr_aligned;
if (addr) {
trcVerbose("mmap-allocated " PTR_FORMAT " .. " PTR_FORMAT " (" UINTX_FORMAT " bytes)",
p2i(addr), p2i(addr + bytes), bytes);
} else {
if (requested_addr != NULL) {
trcVerbose("failed to mmap-allocate " UINTX_FORMAT " bytes at wish address " PTR_FORMAT ".", bytes, p2i(requested_addr));
} else {
trcVerbose("failed to mmap-allocate " UINTX_FORMAT " bytes at any address.", bytes);
}
}
// bookkeeping
vmembk_add(addr, size, 4*K, VMEM_MAPPED);
// Test alignment, see above.
assert0(is_aligned_to(addr, os::vm_page_size()));
return addr;
}
static bool release_mmaped_memory(char* addr, size_t size) {
assert0(is_aligned_to(addr, os::vm_page_size()));
assert0(is_aligned_to(size, os::vm_page_size()));
trcVerbose("release_mmaped_memory [" PTR_FORMAT " - " PTR_FORMAT "].",
p2i(addr), p2i(addr + size - 1));
bool rc = false;
if (::munmap(addr, size) != 0) {
trcVerbose("failed (%d)\n", errno);
rc = false;
} else {
trcVerbose("ok.");
rc = true;
}
return rc;
}
static bool uncommit_mmaped_memory(char* addr, size_t size) {
assert0(is_aligned_to(addr, os::vm_page_size()));
assert0(is_aligned_to(size, os::vm_page_size()));
trcVerbose("uncommit_mmaped_memory [" PTR_FORMAT " - " PTR_FORMAT "].",
p2i(addr), p2i(addr + size - 1));
bool rc = false;
// Uncommit mmap memory with msync MS_INVALIDATE.
if (::msync(addr, size, MS_INVALIDATE) != 0) {
trcVerbose("failed (%d)\n", errno);
rc = false;
} else {
trcVerbose("ok.");
rc = true;
}
return rc;
}
int os::vm_page_size() {
// Seems redundant as all get out.
assert(os::Aix::page_size() != -1, "must call os::init");
return os::Aix::page_size();
}
// Aix allocates memory by pages.
int os::vm_allocation_granularity() {
assert(os::Aix::page_size() != -1, "must call os::init");
return os::Aix::page_size();
}
#ifdef PRODUCT
static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
int err) {
warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
", %d) failed; error='%s' (errno=%d)", p2i(addr), size, exec,
os::errno_name(err), err);
}
#endif
void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
const char* mesg) {
assert(mesg != NULL, "mesg must be specified");
if (!pd_commit_memory(addr, size, exec)) {
// Add extra info in product mode for vm_exit_out_of_memory():
PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg);
}
}
bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
assert(is_aligned_to(addr, os::vm_page_size()),
"addr " PTR_FORMAT " not aligned to vm_page_size (" PTR_FORMAT ")",
p2i(addr), os::vm_page_size());
assert(is_aligned_to(size, os::vm_page_size()),
"size " PTR_FORMAT " not aligned to vm_page_size (" PTR_FORMAT ")",
size, os::vm_page_size());
vmembk_t* const vmi = vmembk_find(addr);
guarantee0(vmi);
vmi->assert_is_valid_subrange(addr, size);
trcVerbose("commit_memory [" PTR_FORMAT " - " PTR_FORMAT "].", p2i(addr), p2i(addr + size - 1));
if (UseExplicitCommit) {
// AIX commits memory on touch. So, touch all pages to be committed.
for (char* p = addr; p < (addr + size); p += 4*K) {
*p = '\0';
}
}
return true;
}
bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint, bool exec) {
return pd_commit_memory(addr, size, exec);
}
void os::pd_commit_memory_or_exit(char* addr, size_t size,
size_t alignment_hint, bool exec,
const char* mesg) {
// Alignment_hint is ignored on this OS.
pd_commit_memory_or_exit(addr, size, exec, mesg);
}
bool os::pd_uncommit_memory(char* addr, size_t size) {
assert(is_aligned_to(addr, os::vm_page_size()),
"addr " PTR_FORMAT " not aligned to vm_page_size (" PTR_FORMAT ")",
p2i(addr), os::vm_page_size());
assert(is_aligned_to(size, os::vm_page_size()),
"size " PTR_FORMAT " not aligned to vm_page_size (" PTR_FORMAT ")",
size, os::vm_page_size());
// Dynamically do different things for mmap/shmat.
const vmembk_t* const vmi = vmembk_find(addr);
guarantee0(vmi);
vmi->assert_is_valid_subrange(addr, size);
if (vmi->type == VMEM_SHMATED) {
return uncommit_shmated_memory(addr, size);
} else {
return uncommit_mmaped_memory(addr, size);
}
}
bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
// Do not call this; no need to commit stack pages on AIX.
ShouldNotReachHere();
return true;
}
bool os::remove_stack_guard_pages(char* addr, size_t size) {
// Do not call this; no need to commit stack pages on AIX.
ShouldNotReachHere();
return true;
}
void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
}
void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
}
void os::numa_make_global(char *addr, size_t bytes) {
}
void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
}
bool os::numa_topology_changed() {
return false;
}
size_t os::numa_get_groups_num() {
return 1;
}
int os::numa_get_group_id() {
return 0;
}
size_t os::numa_get_leaf_groups(int *ids, size_t size) {
if (size > 0) {
ids[0] = 0;
return 1;
}
return 0;
}
int os::numa_get_group_id_for_address(const void* address) {
return 0;
}
bool os::get_page_info(char *start, page_info* info) {
return false;
}
char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
return end;
}
// Reserves and attaches a shared memory segment.
// Will assert if a wish address is given and could not be obtained.
char* os::pd_reserve_memory(size_t bytes, char* requested_addr, size_t alignment_hint) {
// All other Unices do a mmap(MAP_FIXED) if the addr is given,
// thereby clobbering old mappings at that place. That is probably
// not intended, never used and almost certainly an error were it
// ever be used this way (to try attaching at a specified address
// without clobbering old mappings an alternate API exists,
// os::attempt_reserve_memory_at()).
// Instead of mimicking the dangerous coding of the other platforms, here I
// just ignore the request address (release) or assert(debug).
assert0(requested_addr == NULL);
// Always round to os::vm_page_size(), which may be larger than 4K.
bytes = align_up(bytes, os::vm_page_size());
const size_t alignment_hint0 =
alignment_hint ? align_up(alignment_hint, os::vm_page_size()) : 0;
// In 4K mode always use mmap.
// In 64K mode allocate small sizes with mmap, large ones with 64K shmatted.
if (os::vm_page_size() == 4*K) {
return reserve_mmaped_memory(bytes, requested_addr, alignment_hint);
} else {
if (bytes >= Use64KPagesThreshold) {
return reserve_shmated_memory(bytes, requested_addr, alignment_hint);
} else {
return reserve_mmaped_memory(bytes, requested_addr, alignment_hint);
}
}
}
bool os::pd_release_memory(char* addr, size_t size) {
// Dynamically do different things for mmap/shmat.
vmembk_t* const vmi = vmembk_find(addr);
guarantee0(vmi);
// Always round to os::vm_page_size(), which may be larger than 4K.
size = align_up(size, os::vm_page_size());
addr = align_up(addr, os::vm_page_size());
bool rc = false;
bool remove_bookkeeping = false;
if (vmi->type == VMEM_SHMATED) {
// For shmatted memory, we do:
// - If user wants to release the whole range, release the memory (shmdt).
// - If user only wants to release a partial range, uncommit (disclaim) that
// range. That way, at least, we do not use memory anymore (bust still page
// table space).
vmi->assert_is_valid_subrange(addr, size);
if (addr == vmi->addr && size == vmi->size) {
rc = release_shmated_memory(addr, size);
remove_bookkeeping = true;
} else {
rc = uncommit_shmated_memory(addr, size);
}
} else {
// User may unmap partial regions but region has to be fully contained.
#ifdef ASSERT
vmi->assert_is_valid_subrange(addr, size);
#endif
rc = release_mmaped_memory(addr, size);
remove_bookkeeping = true;
}
// update bookkeeping
if (rc && remove_bookkeeping) {
vmembk_remove(vmi);
}
return rc;
}
static bool checked_mprotect(char* addr, size_t size, int prot) {
// Little problem here: if SPEC1170 behaviour is off, mprotect() on AIX will
// not tell me if protection failed when trying to protect an un-protectable range.
//
// This means if the memory was allocated using shmget/shmat, protection wont work
// but mprotect will still return 0:
//
// See http://publib.boulder.ibm.com/infocenter/pseries/v5r3/index.jsp?topic=/com.ibm.aix.basetechref/doc/basetrf1/mprotect.htm
Events::log(NULL, "Protecting memory [" INTPTR_FORMAT "," INTPTR_FORMAT "] with protection modes %x", p2i(addr), p2i(addr+size), prot);
bool rc = ::mprotect(addr, size, prot) == 0 ? true : false;
if (!rc) {
const char* const s_errno = os::errno_name(errno);
warning("mprotect(" PTR_FORMAT "-" PTR_FORMAT ", 0x%X) failed (%s).", addr, addr + size, prot, s_errno);
return false;
}
// mprotect success check
//
// Mprotect said it changed the protection but can I believe it?
//
// To be sure I need to check the protection afterwards. Try to
// read from protected memory and check whether that causes a segfault.
//
if (!os::Aix::xpg_sus_mode()) {
if (CanUseSafeFetch32()) {
const bool read_protected =
(SafeFetch32((int*)addr, 0x12345678) == 0x12345678 &&
SafeFetch32((int*)addr, 0x76543210) == 0x76543210) ? true : false;
if (prot & PROT_READ) {
rc = !read_protected;
} else {
rc = read_protected;
}
if (!rc) {
if (os::Aix::on_pase()) {
// There is an issue on older PASE systems where mprotect() will return success but the
// memory will not be protected.
// This has nothing to do with the problem of using mproect() on SPEC1170 incompatible
// machines; we only see it rarely, when using mprotect() to protect the guard page of
// a stack. It is an OS error.
//
// A valid strategy is just to try again. This usually works. :-/
::usleep(1000);
Events::log(NULL, "Protecting memory [" INTPTR_FORMAT "," INTPTR_FORMAT "] with protection modes %x", p2i(addr), p2i(addr+size), prot);
if (::mprotect(addr, size, prot) == 0) {
const bool read_protected_2 =
(SafeFetch32((int*)addr, 0x12345678) == 0x12345678 &&
SafeFetch32((int*)addr, 0x76543210) == 0x76543210) ? true : false;
rc = true;
}
}
}
}
}
assert(rc == true, "mprotect failed.");
return rc;
}
// Set protections specified
bool os::protect_memory(char* addr, size_t size, ProtType prot, bool is_committed) {
unsigned int p = 0;
switch (prot) {
case MEM_PROT_NONE: p = PROT_NONE; break;
case MEM_PROT_READ: p = PROT_READ; break;
case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
default:
ShouldNotReachHere();
}
// is_committed is unused.
return checked_mprotect(addr, size, p);
}
bool os::guard_memory(char* addr, size_t size) {
return checked_mprotect(addr, size, PROT_NONE);
}
bool os::unguard_memory(char* addr, size_t size) {
return checked_mprotect(addr, size, PROT_READ|PROT_WRITE|PROT_EXEC);
}
// Large page support
static size_t _large_page_size = 0;
// Enable large page support if OS allows that.
void os::large_page_init() {
return; // Nothing to do. See query_multipage_support and friends.
}
char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
// reserve_memory_special() is used to allocate large paged memory. On AIX, we implement
// 64k paged memory reservation using the normal memory allocation paths (os::reserve_memory()),
// so this is not needed.
assert(false, "should not be called on AIX");
return NULL;
}
bool os::release_memory_special(char* base, size_t bytes) {
// Detaching the SHM segment will also delete it, see reserve_memory_special().
Unimplemented();
return false;
}
size_t os::large_page_size() {
return _large_page_size;
}
bool os::can_commit_large_page_memory() {
// Does not matter, we do not support huge pages.
return false;
}
bool os::can_execute_large_page_memory() {
// Does not matter, we do not support huge pages.
return false;
}
char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr, int file_desc) {
assert(file_desc >= 0, "file_desc is not valid");
char* result = NULL;
// Always round to os::vm_page_size(), which may be larger than 4K.
bytes = align_up(bytes, os::vm_page_size());
result = reserve_mmaped_memory(bytes, requested_addr, 0);
if (result != NULL) {
if (replace_existing_mapping_with_file_mapping(result, bytes, file_desc) == NULL) {
vm_exit_during_initialization(err_msg("Error in mapping Java heap at the given filesystem directory"));
}
}
return result;
}
// Reserve memory at an arbitrary address, only if that area is
// available (and not reserved for something else).
char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
char* addr = NULL;
// Always round to os::vm_page_size(), which may be larger than 4K.
bytes = align_up(bytes, os::vm_page_size());
// In 4K mode always use mmap.
// In 64K mode allocate small sizes with mmap, large ones with 64K shmatted.
if (os::vm_page_size() == 4*K) {
return reserve_mmaped_memory(bytes, requested_addr, 0);
} else {
if (bytes >= Use64KPagesThreshold) {
return reserve_shmated_memory(bytes, requested_addr, 0);
} else {
return reserve_mmaped_memory(bytes, requested_addr, 0);
}
}
return addr;
}
// Sleep forever; naked call to OS-specific sleep; use with CAUTION
void os::infinite_sleep() {
while (true) { // sleep forever ...
::sleep(100); // ... 100 seconds at a time
}
}
// Used to convert frequent JVM_Yield() to nops
bool os::dont_yield() {
return DontYieldALot;
}
void os::naked_yield() {
sched_yield();
}
////////////////////////////////////////////////////////////////////////////////
// thread priority support
// From AIX manpage to pthread_setschedparam
// (see: http://publib.boulder.ibm.com/infocenter/pseries/v5r3/index.jsp?
// topic=/com.ibm.aix.basetechref/doc/basetrf1/pthread_setschedparam.htm):
//
// "If schedpolicy is SCHED_OTHER, then sched_priority must be in the
// range from 40 to 80, where 40 is the least favored priority and 80
// is the most favored."
//
// (Actually, I doubt this even has an impact on AIX, as we do kernel
// scheduling there; however, this still leaves iSeries.)
//
// We use the same values for AIX and PASE.
int os::java_to_os_priority[CriticalPriority + 1] = {
54, // 0 Entry should never be used
55, // 1 MinPriority
55, // 2
56, // 3
56, // 4
57, // 5 NormPriority
57, // 6
58, // 7
58, // 8
59, // 9 NearMaxPriority
60, // 10 MaxPriority
60 // 11 CriticalPriority
};
static int prio_init() {
if (ThreadPriorityPolicy == 1) {
if (geteuid() != 0) {
if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
warning("-XX:ThreadPriorityPolicy=1 may require system level permission, " \
"e.g., being the root user. If the necessary permission is not " \
"possessed, changes to priority will be silently ignored.");
}
}
}
if (UseCriticalJavaThreadPriority) {
os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
}
return 0;
}
OSReturn os::set_native_priority(Thread* thread, int newpri) {
if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK;
pthread_t thr = thread->osthread()->pthread_id();
int policy = SCHED_OTHER;
struct sched_param param;
param.sched_priority = newpri;
int ret = pthread_setschedparam(thr, policy, ¶m);
if (ret != 0) {
trcVerbose("Could not change priority for thread %d to %d (error %d, %s)",
(int)thr, newpri, ret, os::errno_name(ret));
}
return (ret == 0) ? OS_OK : OS_ERR;
}
OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
if (!UseThreadPriorities || ThreadPriorityPolicy == 0) {
*priority_ptr = java_to_os_priority[NormPriority];
return OS_OK;
}
pthread_t thr = thread->osthread()->pthread_id();
int policy = SCHED_OTHER;
struct sched_param param;
int ret = pthread_getschedparam(thr, &policy, ¶m);
*priority_ptr = param.sched_priority;
return (ret == 0) ? OS_OK : OS_ERR;
}
////////////////////////////////////////////////////////////////////////////////
// suspend/resume support
// The low-level signal-based suspend/resume support is a remnant from the
// old VM-suspension that used to be for java-suspension, safepoints etc,
// within hotspot. Currently used by JFR's OSThreadSampler
//
// The remaining code is greatly simplified from the more general suspension
// code that used to be used.
//
// The protocol is quite simple:
// - suspend:
// - sends a signal to the target thread
// - polls the suspend state of the osthread using a yield loop
// - target thread signal handler (SR_handler) sets suspend state
// and blocks in sigsuspend until continued
// - resume:
// - sets target osthread state to continue
// - sends signal to end the sigsuspend loop in the SR_handler
//
// Note that the SR_lock plays no role in this suspend/resume protocol,
// but is checked for NULL in SR_handler as a thread termination indicator.
// The SR_lock is, however, used by JavaThread::java_suspend()/java_resume() APIs.
//
// Note that resume_clear_context() and suspend_save_context() are needed
// by SR_handler(), so that fetch_frame_from_ucontext() works,
// which in part is used by:
// - Forte Analyzer: AsyncGetCallTrace()
// - StackBanging: get_frame_at_stack_banging_point()
static void resume_clear_context(OSThread *osthread) {
osthread->set_ucontext(NULL);
osthread->set_siginfo(NULL);
}
static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
osthread->set_ucontext(context);
osthread->set_siginfo(siginfo);
}
//
// Handler function invoked when a thread's execution is suspended or
// resumed. We have to be careful that only async-safe functions are
// called here (Note: most pthread functions are not async safe and
// should be avoided.)
//
// Note: sigwait() is a more natural fit than sigsuspend() from an
// interface point of view, but sigwait() prevents the signal hander
// from being run. libpthread would get very confused by not having
// its signal handlers run and prevents sigwait()'s use with the
// mutex granting granting signal.
//
// Currently only ever called on the VMThread and JavaThreads (PC sampling).
//
static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
// Save and restore errno to avoid confusing native code with EINTR
// after sigsuspend.
int old_errno = errno;
Thread* thread = Thread::current_or_null_safe();
assert(thread != NULL, "Missing current thread in SR_handler");
// On some systems we have seen signal delivery get "stuck" until the signal
// mask is changed as part of thread termination. Check that the current thread
// has not already terminated (via SR_lock()) - else the following assertion
// will fail because the thread is no longer a JavaThread as the ~JavaThread
// destructor has completed.
if (thread->SR_lock() == NULL) {
return;
}
assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
OSThread* osthread = thread->osthread();
os::SuspendResume::State current = osthread->sr.state();
if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
suspend_save_context(osthread, siginfo, context);
// attempt to switch the state, we assume we had a SUSPEND_REQUEST
os::SuspendResume::State state = osthread->sr.suspended();
if (state == os::SuspendResume::SR_SUSPENDED) {
sigset_t suspend_set; // signals for sigsuspend()
sigemptyset(&suspend_set);
// get current set of blocked signals and unblock resume signal
pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
sigdelset(&suspend_set, SR_signum);
// wait here until we are resumed
while (1) {
sigsuspend(&suspend_set);
os::SuspendResume::State result = osthread->sr.running();
if (result == os::SuspendResume::SR_RUNNING) {
break;
}
}
} else if (state == os::SuspendResume::SR_RUNNING) {
// request was cancelled, continue
} else {
ShouldNotReachHere();
}
resume_clear_context(osthread);
} else if (current == os::SuspendResume::SR_RUNNING) {
// request was cancelled, continue
} else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
// ignore
} else {
ShouldNotReachHere();
}
errno = old_errno;
}
static int SR_initialize() {
struct sigaction act;
char *s;
// Get signal number to use for suspend/resume
if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
int sig = ::strtol(s, 0, 10);
if (sig > MAX2(SIGSEGV, SIGBUS) && // See 4355769.
sig < NSIG) { // Must be legal signal and fit into sigflags[].
SR_signum = sig;
} else {
warning("You set _JAVA_SR_SIGNUM=%d. It must be in range [%d, %d]. Using %d instead.",
sig, MAX2(SIGSEGV, SIGBUS)+1, NSIG-1, SR_signum);
}
}
assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
"SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
sigemptyset(&SR_sigset);
sigaddset(&SR_sigset, SR_signum);
// Set up signal handler for suspend/resume.
act.sa_flags = SA_RESTART|SA_SIGINFO;
act.sa_handler = (void (*)(int)) SR_handler;
// SR_signum is blocked by default.
pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
if (sigaction(SR_signum, &act, 0) == -1) {
return -1;
}
// Save signal flag
os::Aix::set_our_sigflags(SR_signum, act.sa_flags);
return 0;
}
static int SR_finalize() {
return 0;
}
static int sr_notify(OSThread* osthread) {
int status = pthread_kill(osthread->pthread_id(), SR_signum);
assert_status(status == 0, status, "pthread_kill");
return status;
}
// "Randomly" selected value for how long we want to spin
// before bailing out on suspending a thread, also how often
// we send a signal to a thread we want to resume
static const int RANDOMLY_LARGE_INTEGER = 1000000;
static const int RANDOMLY_LARGE_INTEGER2 = 100;
// returns true on success and false on error - really an error is fatal
// but this seems the normal response to library errors
static bool do_suspend(OSThread* osthread) {
assert(osthread->sr.is_running(), "thread should be running");
// mark as suspended and send signal
if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
// failed to switch, state wasn't running?
ShouldNotReachHere();
return false;
}
if (sr_notify(osthread) != 0) {
// try to cancel, switch to running
os::SuspendResume::State result = osthread->sr.cancel_suspend();
if (result == os::SuspendResume::SR_RUNNING) {
// cancelled
return false;
} else if (result == os::SuspendResume::SR_SUSPENDED) {
// somehow managed to suspend
return true;
} else {
ShouldNotReachHere();
return false;
}
}
// managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
for (int n = 0; !osthread->sr.is_suspended(); n++) {
for (int i = 0; i < RANDOMLY_LARGE_INTEGER2 && !osthread->sr.is_suspended(); i++) {
os::naked_yield();
}
// timeout, try to cancel the request
if (n >= RANDOMLY_LARGE_INTEGER) {
os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
if (cancelled == os::SuspendResume::SR_RUNNING) {
return false;
} else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
return true;
} else {
ShouldNotReachHere();
return false;
}
}
}
guarantee(osthread->sr.is_suspended(), "Must be suspended");
return true;
}
static void do_resume(OSThread* osthread) {
//assert(osthread->sr.is_suspended(), "thread should be suspended");
if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
// failed to switch to WAKEUP_REQUEST
ShouldNotReachHere();
return;
}
while (!osthread->sr.is_running()) {
if (sr_notify(osthread) == 0) {
for (int n = 0; n < RANDOMLY_LARGE_INTEGER && !osthread->sr.is_running(); n++) {
for (int i = 0; i < 100 && !osthread->sr.is_running(); i++) {
os::naked_yield();
}
}
} else {
ShouldNotReachHere();
}
}
guarantee(osthread->sr.is_running(), "Must be running!");
}
///////////////////////////////////////////////////////////////////////////////////
// signal handling (except suspend/resume)
// This routine may be used by user applications as a "hook" to catch signals.
// The user-defined signal handler must pass unrecognized signals to this
// routine, and if it returns true (non-zero), then the signal handler must
// return immediately. If the flag "abort_if_unrecognized" is true, then this
// routine will never retun false (zero), but instead will execute a VM panic
// routine kill the process.
//
// If this routine returns false, it is OK to call it again. This allows
// the user-defined signal handler to perform checks either before or after
// the VM performs its own checks. Naturally, the user code would be making
// a serious error if it tried to handle an exception (such as a null check
// or breakpoint) that the VM was generating for its own correct operation.
//
// This routine may recognize any of the following kinds of signals:
// SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
// It should be consulted by handlers for any of those signals.
//
// The caller of this routine must pass in the three arguments supplied
// to the function referred to in the "sa_sigaction" (not the "sa_handler")
// field of the structure passed to sigaction(). This routine assumes that
// the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
//
// Note that the VM will print warnings if it detects conflicting signal
// handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
//
extern "C" JNIEXPORT int
JVM_handle_aix_signal(int signo, siginfo_t* siginfo, void* ucontext, int abort_if_unrecognized);
// Set thread signal mask (for some reason on AIX sigthreadmask() seems
// to be the thing to call; documentation is not terribly clear about whether
// pthread_sigmask also works, and if it does, whether it does the same.
bool set_thread_signal_mask(int how, const sigset_t* set, sigset_t* oset) {
const int rc = ::pthread_sigmask(how, set, oset);
// return value semantics differ slightly for error case:
// pthread_sigmask returns error number, sigthreadmask -1 and sets global errno
// (so, pthread_sigmask is more theadsafe for error handling)
// But success is always 0.
return rc == 0 ? true : false;
}
// Function to unblock all signals which are, according
// to POSIX, typical program error signals. If they happen while being blocked,
// they typically will bring down the process immediately.
bool unblock_program_error_signals() {
sigset_t set;
::sigemptyset(&set);
::sigaddset(&set, SIGILL);
::sigaddset(&set, SIGBUS);
::sigaddset(&set, SIGFPE);
::sigaddset(&set, SIGSEGV);
return set_thread_signal_mask(SIG_UNBLOCK, &set, NULL);
}
// Renamed from 'signalHandler' to avoid collision with other shared libs.
static void javaSignalHandler(int sig, siginfo_t* info, void* uc) {
assert(info != NULL && uc != NULL, "it must be old kernel");
// Never leave program error signals blocked;
// on all our platforms they would bring down the process immediately when
// getting raised while being blocked.
unblock_program_error_signals();
int orig_errno = errno; // Preserve errno value over signal handler.
JVM_handle_aix_signal(sig, info, uc, true);
errno = orig_errno;
}
// This boolean allows users to forward their own non-matching signals
// to JVM_handle_aix_signal, harmlessly.
bool os::Aix::signal_handlers_are_installed = false;
// For signal-chaining
bool os::Aix::libjsig_is_loaded = false;
typedef struct sigaction *(*get_signal_t)(int);
get_signal_t os::Aix::get_signal_action = NULL;
struct sigaction* os::Aix::get_chained_signal_action(int sig) {
struct sigaction *actp = NULL;
if (libjsig_is_loaded) {
// Retrieve the old signal handler from libjsig
actp = (*get_signal_action)(sig);
}
if (actp == NULL) {
// Retrieve the preinstalled signal handler from jvm
actp = os::Posix::get_preinstalled_handler(sig);
}
return actp;
}
static bool call_chained_handler(struct sigaction *actp, int sig,
siginfo_t *siginfo, void *context) {
// Call the old signal handler
if (actp->sa_handler == SIG_DFL) {
// It's more reasonable to let jvm treat it as an unexpected exception
// instead of taking the default action.
return false;
} else if (actp->sa_handler != SIG_IGN) {
if ((actp->sa_flags & SA_NODEFER) == 0) {
// automaticlly block the signal
sigaddset(&(actp->sa_mask), sig);
}
sa_handler_t hand = NULL;
sa_sigaction_t sa = NULL;
bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
// retrieve the chained handler
if (siginfo_flag_set) {
sa = actp->sa_sigaction;
} else {
hand = actp->sa_handler;
}
if ((actp->sa_flags & SA_RESETHAND) != 0) {
actp->sa_handler = SIG_DFL;
}
// try to honor the signal mask
sigset_t oset;
sigemptyset(&oset);
pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
// call into the chained handler
if (siginfo_flag_set) {
(*sa)(sig, siginfo, context);
} else {
(*hand)(sig);
}
// restore the signal mask
pthread_sigmask(SIG_SETMASK, &oset, NULL);
}
// Tell jvm's signal handler the signal is taken care of.
return true;
}
bool os::Aix::chained_handler(int sig, siginfo_t* siginfo, void* context) {
bool chained = false;
// signal-chaining
if (UseSignalChaining) {
struct sigaction *actp = get_chained_signal_action(sig);
if (actp != NULL) {
chained = call_chained_handler(actp, sig, siginfo, context);
}
}
return chained;
}
// for diagnostic
int sigflags[NSIG];
int os::Aix::get_our_sigflags(int sig) {
assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
return sigflags[sig];
}
void os::Aix::set_our_sigflags(int sig, int flags) {
assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
if (sig > 0 && sig < NSIG) {
sigflags[sig] = flags;
}
}
void os::Aix::set_signal_handler(int sig, bool set_installed) {
// Check for overwrite.
struct sigaction oldAct;
sigaction(sig, (struct sigaction*)NULL, &oldAct);
void* oldhand = oldAct.sa_sigaction
? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
: CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)javaSignalHandler)) {
if (AllowUserSignalHandlers || !set_installed) {
// Do not overwrite; user takes responsibility to forward to us.
return;
} else if (UseSignalChaining) {
// save the old handler in jvm
os::Posix::save_preinstalled_handler(sig, oldAct);
// libjsig also interposes the sigaction() call below and saves the
// old sigaction on it own.
} else {
fatal("Encountered unexpected pre-existing sigaction handler "
"%#lx for signal %d.", (long)oldhand, sig);
}
}
struct sigaction sigAct;
sigfillset(&(sigAct.sa_mask));
if (!set_installed) {
sigAct.sa_handler = SIG_DFL;
sigAct.sa_flags = SA_RESTART;
} else {
sigAct.sa_sigaction = javaSignalHandler;
sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
}
// Save flags, which are set by ours
assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
sigflags[sig] = sigAct.sa_flags;
int ret = sigaction(sig, &sigAct, &oldAct);
assert(ret == 0, "check");
void* oldhand2 = oldAct.sa_sigaction
? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
: CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
assert(oldhand2 == oldhand, "no concurrent signal handler installation");
}
// install signal handlers for signals that HotSpot needs to
// handle in order to support Java-level exception handling.
void os::Aix::install_signal_handlers() {
if (!signal_handlers_are_installed) {
signal_handlers_are_installed = true;
// signal-chaining
typedef void (*signal_setting_t)();
signal_setting_t begin_signal_setting = NULL;
signal_setting_t end_signal_setting = NULL;
begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
if (begin_signal_setting != NULL) {
end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
get_signal_action = CAST_TO_FN_PTR(get_signal_t,
dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
libjsig_is_loaded = true;
assert(UseSignalChaining, "should enable signal-chaining");
}
if (libjsig_is_loaded) {
// Tell libjsig jvm is setting signal handlers.
(*begin_signal_setting)();
}
set_signal_handler(SIGSEGV, true);
set_signal_handler(SIGPIPE, true);
set_signal_handler(SIGBUS, true);
set_signal_handler(SIGILL, true);
set_signal_handler(SIGFPE, true);
set_signal_handler(SIGTRAP, true);
set_signal_handler(SIGXFSZ, true);
if (libjsig_is_loaded) {
// Tell libjsig jvm finishes setting signal handlers.
(*end_signal_setting)();
}
// We don't activate signal checker if libjsig is in place, we trust ourselves
// and if UserSignalHandler is installed all bets are off.
// Log that signal checking is off only if -verbose:jni is specified.
if (CheckJNICalls) {
if (libjsig_is_loaded) {
tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
check_signals = false;
}
if (AllowUserSignalHandlers) {
tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
check_signals = false;
}
// Need to initialize check_signal_done.
::sigemptyset(&check_signal_done);
}
}
}
static const char* get_signal_handler_name(address handler,
char* buf, int buflen) {
int offset;
bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
if (found) {
// skip directory names
const char *p1, *p2;
p1 = buf;
size_t len = strlen(os::file_separator());
while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
// The way os::dll_address_to_library_name is implemented on Aix
// right now, it always returns -1 for the offset which is not
// terribly informative.
// Will fix that. For now, omit the offset.
jio_snprintf(buf, buflen, "%s", p1);
} else {
jio_snprintf(buf, buflen, PTR_FORMAT, handler);
}
return buf;
}
static void print_signal_handler(outputStream* st, int sig,
char* buf, size_t buflen) {
struct sigaction sa;
sigaction(sig, NULL, &sa);
st->print("%s: ", os::exception_name(sig, buf, buflen));
address handler = (sa.sa_flags & SA_SIGINFO)
? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
: CAST_FROM_FN_PTR(address, sa.sa_handler);
if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
st->print("SIG_DFL");
} else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
st->print("SIG_IGN");
} else {
st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
}
// Print readable mask.
st->print(", sa_mask[0]=");
os::Posix::print_signal_set_short(st, &sa.sa_mask);
address rh = VMError::get_resetted_sighandler(sig);
// May be, handler was resetted by VMError?
if (rh != NULL) {
handler = rh;
sa.sa_flags = VMError::get_resetted_sigflags(sig);
}
// Print textual representation of sa_flags.
st->print(", sa_flags=");
os::Posix::print_sa_flags(st, sa.sa_flags);
// Check: is it our handler?
if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)javaSignalHandler) ||
handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
// It is our signal handler.
// Check for flags, reset system-used one!
if ((int)sa.sa_flags != os::Aix::get_our_sigflags(sig)) {
st->print(", flags was changed from " PTR32_FORMAT ", consider using jsig library",
os::Aix::get_our_sigflags(sig));
}
}
st->cr();
}
#define DO_SIGNAL_CHECK(sig) \
if (!sigismember(&check_signal_done, sig)) \
os::Aix::check_signal_handler(sig)
// This method is a periodic task to check for misbehaving JNI applications
// under CheckJNI, we can add any periodic checks here
void os::run_periodic_checks() {
if (check_signals == false) return;
// SEGV and BUS if overridden could potentially prevent
// generation of hs*.log in the event of a crash, debugging
// such a case can be very challenging, so we absolutely
// check the following for a good measure:
DO_SIGNAL_CHECK(SIGSEGV);
DO_SIGNAL_CHECK(SIGILL);
DO_SIGNAL_CHECK(SIGFPE);
DO_SIGNAL_CHECK(SIGBUS);
DO_SIGNAL_CHECK(SIGPIPE);
DO_SIGNAL_CHECK(SIGXFSZ);
if (UseSIGTRAP) {
DO_SIGNAL_CHECK(SIGTRAP);
}
// ReduceSignalUsage allows the user to override these handlers
// see comments at the very top and jvm_md.h
if (!ReduceSignalUsage) {
DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
DO_SIGNAL_CHECK(BREAK_SIGNAL);
}
DO_SIGNAL_CHECK(SR_signum);
}
typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
static os_sigaction_t os_sigaction = NULL;
void os::Aix::check_signal_handler(int sig) {
char buf[O_BUFLEN];
address jvmHandler = NULL;
struct sigaction act;
if (os_sigaction == NULL) {
// only trust the default sigaction, in case it has been interposed
os_sigaction = CAST_TO_FN_PTR(os_sigaction_t, dlsym(RTLD_DEFAULT, "sigaction"));
if (os_sigaction == NULL) return;
}
os_sigaction(sig, (struct sigaction*)NULL, &act);
address thisHandler = (act.sa_flags & SA_SIGINFO)
? CAST_FROM_FN_PTR(address, act.sa_sigaction)
: CAST_FROM_FN_PTR(address, act.sa_handler);
switch(sig) {
case SIGSEGV:
case SIGBUS:
case SIGFPE:
case SIGPIPE:
case SIGILL:
case SIGXFSZ:
jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)javaSignalHandler);
break;
case SHUTDOWN1_SIGNAL:
case SHUTDOWN2_SIGNAL:
case SHUTDOWN3_SIGNAL:
case BREAK_SIGNAL:
jvmHandler = (address)user_handler();
break;
default:
if (sig == SR_signum) {
jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
} else {
return;
}
break;
}
if (thisHandler != jvmHandler) {
tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
// No need to check this sig any longer
sigaddset(&check_signal_done, sig);
// Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN
if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) {
tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell",
exception_name(sig, buf, O_BUFLEN));
}
} else if (os::Aix::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Aix::get_our_sigflags(sig)) {
tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
tty->print("expected:");
os::Posix::print_sa_flags(tty, os::Aix::get_our_sigflags(sig));
tty->cr();
tty->print(" found:");
os::Posix::print_sa_flags(tty, act.sa_flags);
tty->cr();
// No need to check this sig any longer
sigaddset(&check_signal_done, sig);
}
// Dump all the signal
if (sigismember(&check_signal_done, sig)) {
print_signal_handlers(tty, buf, O_BUFLEN);
}
}
// To install functions for atexit system call
extern "C" {
static void perfMemory_exit_helper() {
perfMemory_exit();
}
}
// This is called _before_ the most of global arguments have been parsed.
void os::init(void) {
// This is basic, we want to know if that ever changes.
// (Shared memory boundary is supposed to be a 256M aligned.)
assert(SHMLBA == ((uint64_t)0x10000000ULL)/*256M*/, "unexpected");
// Record process break at startup.
g_brk_at_startup = (address) ::sbrk(0);
assert(g_brk_at_startup != (address) -1, "sbrk failed");
// First off, we need to know whether we run on AIX or PASE, and
// the OS level we run on.
os::Aix::initialize_os_info();
// Scan environment (SPEC1170 behaviour, etc).
os::Aix::scan_environment();
// Probe multipage support.
query_multipage_support();
// Act like we only have one page size by eliminating corner cases which
// we did not support very well anyway.
// We have two input conditions:
// 1) Data segment page size. This is controlled by linker setting (datapsize) on the
// launcher, and/or by LDR_CNTRL environment variable. The latter overrules the linker
// setting.
// Data segment page size is important for us because it defines the thread stack page
// size, which is needed for guard page handling, stack banging etc.
// 2) The ability to allocate 64k pages dynamically. If this is a given, java heap can
// and should be allocated with 64k pages.
//
// So, we do the following:
// LDR_CNTRL can_use_64K_pages_dynamically what we do remarks
// 4K no 4K old systems (aix 5.2, as/400 v5r4) or new systems with AME activated
// 4k yes 64k (treat 4k stacks as 64k) different loader than java and standard settings
// 64k no --- AIX 5.2 ? ---
// 64k yes 64k new systems and standard java loader (we set datapsize=64k when linking)
// We explicitly leave no option to change page size, because only upgrading would work,
// not downgrading (if stack page size is 64k you cannot pretend its 4k).
if (g_multipage_support.datapsize == 4*K) {
// datapsize = 4K. Data segment, thread stacks are 4K paged.
if (g_multipage_support.can_use_64K_pages) {
// .. but we are able to use 64K pages dynamically.
// This would be typical for java launchers which are not linked
// with datapsize=64K (like, any other launcher but our own).
//
// In this case it would be smart to allocate the java heap with 64K
// to get the performance benefit, and to fake 64k pages for the
// data segment (when dealing with thread stacks).
//
// However, leave a possibility to downgrade to 4K, using
// -XX:-Use64KPages.
if (Use64KPages) {
trcVerbose("64K page mode (faked for data segment)");
Aix::_page_size = 64*K;
} else {
trcVerbose("4K page mode (Use64KPages=off)");
Aix::_page_size = 4*K;
}
} else {
// .. and not able to allocate 64k pages dynamically. Here, just
// fall back to 4K paged mode and use mmap for everything.
trcVerbose("4K page mode");
Aix::_page_size = 4*K;
FLAG_SET_ERGO(Use64KPages, false);
}
} else {
// datapsize = 64k. Data segment, thread stacks are 64k paged.
// This normally means that we can allocate 64k pages dynamically.
// (There is one special case where this may be false: EXTSHM=on.
// but we decided to not support that mode).
assert0(g_multipage_support.can_use_64K_pages);
Aix::_page_size = 64*K;
trcVerbose("64K page mode");
FLAG_SET_ERGO(Use64KPages, true);
}
// For now UseLargePages is just ignored.
FLAG_SET_ERGO(UseLargePages, false);
_page_sizes[0] = 0;
// debug trace
trcVerbose("os::vm_page_size %s", describe_pagesize(os::vm_page_size()));
// Next, we need to initialize libo4 and libperfstat libraries.
if (os::Aix::on_pase()) {
os::Aix::initialize_libo4();
} else {
os::Aix::initialize_libperfstat();
}
// Reset the perfstat information provided by ODM.
if (os::Aix::on_aix()) {
libperfstat::perfstat_reset();
}
// Now initialze basic system properties. Note that for some of the values we
// need libperfstat etc.
os::Aix::initialize_system_info();
clock_tics_per_sec = sysconf(_SC_CLK_TCK);
init_random(1234567);
// _main_thread points to the thread that created/loaded the JVM.
Aix::_main_thread = pthread_self();
initial_time_count = javaTimeNanos();
os::Posix::init();
}
// This is called _after_ the global arguments have been parsed.
jint os::init_2(void) {
// This could be set after os::Posix::init() but all platforms
// have to set it the same so we have to mirror Solaris.
DEBUG_ONLY(os::set_mutex_init_done();)
os::Posix::init_2();
if (os::Aix::on_pase()) {
trcVerbose("Running on PASE.");
} else {
trcVerbose("Running on AIX (not PASE).");
}
trcVerbose("processor count: %d", os::_processor_count);
trcVerbose("physical memory: %lu", Aix::_physical_memory);
// Initially build up the loaded dll map.
LoadedLibraries::reload();
if (Verbose) {
trcVerbose("Loaded Libraries: ");
LoadedLibraries::print(tty);
}
// initialize suspend/resume support - must do this before signal_sets_init()
if (SR_initialize() != 0) {
perror("SR_initialize failed");
return JNI_ERR;
}
Aix::signal_sets_init();
Aix::install_signal_handlers();
// Initialize data for jdk.internal.misc.Signal
if (!ReduceSignalUsage) {
jdk_misc_signal_init();
}
// Check and sets minimum stack sizes against command line options
if (Posix::set_minimum_stack_sizes() == JNI_ERR) {
return JNI_ERR;
}
if (UseNUMA) {
UseNUMA = false;
warning("NUMA optimizations are not available on this OS.");
}
if (MaxFDLimit) {
// Set the number of file descriptors to max. print out error
// if getrlimit/setrlimit fails but continue regardless.
struct rlimit nbr_files;
int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
if (status != 0) {
log_info(os)("os::init_2 getrlimit failed: %s", os::strerror(errno));
} else {
nbr_files.rlim_cur = nbr_files.rlim_max;
status = setrlimit(RLIMIT_NOFILE, &nbr_files);
if (status != 0) {
log_info(os)("os::init_2 setrlimit failed: %s", os::strerror(errno));
}
}
}
if (PerfAllowAtExitRegistration) {
// Only register atexit functions if PerfAllowAtExitRegistration is set.
// At exit functions can be delayed until process exit time, which
// can be problematic for embedded VM situations. Embedded VMs should
// call DestroyJavaVM() to assure that VM resources are released.
// Note: perfMemory_exit_helper atexit function may be removed in
// the future if the appropriate cleanup code can be added to the
// VM_Exit VMOperation's doit method.
if (atexit(perfMemory_exit_helper) != 0) {
warning("os::init_2 atexit(perfMemory_exit_helper) failed");
}
}
// initialize thread priority policy
prio_init();
return JNI_OK;
}
// Mark the polling page as unreadable
void os::make_polling_page_unreadable(void) {
if (!guard_memory((char*)_polling_page, Aix::page_size())) {
fatal("Could not disable polling page");
}
};
// Mark the polling page as readable
void os::make_polling_page_readable(void) {
// Changed according to os_linux.cpp.
if (!checked_mprotect((char *)_polling_page, Aix::page_size(), PROT_READ)) {
fatal("Could not enable polling page at " PTR_FORMAT, _polling_page);
}
};
int os::active_processor_count() {
// User has overridden the number of active processors
if (ActiveProcessorCount > 0) {
log_trace(os)("active_processor_count: "
"active processor count set by user : %d",
ActiveProcessorCount);
return ActiveProcessorCount;
}
int online_cpus = ::sysconf(_SC_NPROCESSORS_ONLN);
assert(online_cpus > 0 && online_cpus <= processor_count(), "sanity check");
return online_cpus;
}
void os::set_native_thread_name(const char *name) {
// Not yet implemented.
return;
}
bool os::bind_to_processor(uint processor_id) {
// Not yet implemented.
return false;
}
void os::SuspendedThreadTask::internal_do_task() {
if (do_suspend(_thread->osthread())) {
SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
do_task(context);
do_resume(_thread->osthread());
}
}
////////////////////////////////////////////////////////////////////////////////
// debug support
bool os::find(address addr, outputStream* st) {
st->print(PTR_FORMAT ": ", addr);
loaded_module_t lm;
if (LoadedLibraries::find_for_text_address(addr, &lm) != NULL ||
LoadedLibraries::find_for_data_address(addr, &lm) != NULL) {
st->print_cr("%s", lm.path);
return true;
}
return false;
}
////////////////////////////////////////////////////////////////////////////////
// misc
// This does not do anything on Aix. This is basically a hook for being
// able to use structured exception handling (thread-local exception filters)
// on, e.g., Win32.
void
os::os_exception_wrapper(java_call_t f, JavaValue* value, const methodHandle& method,
JavaCallArguments* args, Thread* thread) {
f(value, method, args, thread);
}
void os::print_statistics() {
}
bool os::message_box(const char* title, const char* message) {
int i;
fdStream err(defaultStream::error_fd());
for (i = 0; i < 78; i++) err.print_raw("=");
err.cr();
err.print_raw_cr(title);
for (i = 0; i < 78; i++) err.print_raw("-");
err.cr();
err.print_raw_cr(message);
for (i = 0; i < 78; i++) err.print_raw("=");
err.cr();
char buf[16];
// Prevent process from exiting upon "read error" without consuming all CPU
while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
return buf[0] == 'y' || buf[0] == 'Y';
}
// Is a (classpath) directory empty?
bool os::dir_is_empty(const char* path) {
DIR *dir = NULL;
struct dirent *ptr;
dir = opendir(path);
if (dir == NULL) return true;
/* Scan the directory */
bool result = true;
while (result && (ptr = readdir(dir)) != NULL) {
if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
result = false;
}
}
closedir(dir);
return result;
}
// This code originates from JDK's sysOpen and open64_w
// from src/solaris/hpi/src/system_md.c
int os::open(const char *path, int oflag, int mode) {
if (strlen(path) > MAX_PATH - 1) {
errno = ENAMETOOLONG;
return -1;
}
int fd;
fd = ::open64(path, oflag, mode);
if (fd == -1) return -1;
// If the open succeeded, the file might still be a directory.
{
struct stat64 buf64;
int ret = ::fstat64(fd, &buf64);
int st_mode = buf64.st_mode;
if (ret != -1) {
if ((st_mode & S_IFMT) == S_IFDIR) {
errno = EISDIR;
::close(fd);
return -1;
}
} else {
::close(fd);
return -1;
}
}
// All file descriptors that are opened in the JVM and not
// specifically destined for a subprocess should have the
// close-on-exec flag set. If we don't set it, then careless 3rd
// party native code might fork and exec without closing all
// appropriate file descriptors (e.g. as we do in closeDescriptors in
// UNIXProcess.c), and this in turn might:
//
// - cause end-of-file to fail to be detected on some file
// descriptors, resulting in mysterious hangs, or
//
// - might cause an fopen in the subprocess to fail on a system
// suffering from bug 1085341.
//
// (Yes, the default setting of the close-on-exec flag is a Unix
// design flaw.)
//
// See:
// 1085341: 32-bit stdio routines should support file descriptors >255
// 4843136: (process) pipe file descriptor from Runtime.exec not being closed
// 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
#ifdef FD_CLOEXEC
{
int flags = ::fcntl(fd, F_GETFD);
if (flags != -1)
::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
}
#endif
return fd;
}
// create binary file, rewriting existing file if required
int os::create_binary_file(const char* path, bool rewrite_existing) {
int oflags = O_WRONLY | O_CREAT;
if (!rewrite_existing) {
oflags |= O_EXCL;
}
return ::open64(path, oflags, S_IREAD | S_IWRITE);
}
// return current position of file pointer
jlong os::current_file_offset(int fd) {
return (jlong)::lseek64(fd, (off64_t)0, SEEK_CUR);
}
// move file pointer to the specified offset
jlong os::seek_to_file_offset(int fd, jlong offset) {
return (jlong)::lseek64(fd, (off64_t)offset, SEEK_SET);
}
// This code originates from JDK's sysAvailable
// from src/solaris/hpi/src/native_threads/src/sys_api_td.c
int os::available(int fd, jlong *bytes) {
jlong cur, end;
int mode;
struct stat64 buf64;
if (::fstat64(fd, &buf64) >= 0) {
mode = buf64.st_mode;
if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
int n;
if (::ioctl(fd, FIONREAD, &n) >= 0) {
*bytes = n;
return 1;
}
}
}
if ((cur = ::lseek64(fd, 0L, SEEK_CUR)) == -1) {
return 0;
} else if ((end = ::lseek64(fd, 0L, SEEK_END)) == -1) {
return 0;
} else if (::lseek64(fd, cur, SEEK_SET) == -1) {
return 0;
}
*bytes = end - cur;
return 1;
}
// Map a block of memory.
char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
char *addr, size_t bytes, bool read_only,
bool allow_exec) {
int prot;
int flags = MAP_PRIVATE;
if (read_only) {
prot = PROT_READ;
flags = MAP_SHARED;
} else {
prot = PROT_READ | PROT_WRITE;
flags = MAP_PRIVATE;
}
if (allow_exec) {
prot |= PROT_EXEC;
}
if (addr != NULL) {
flags |= MAP_FIXED;
}
// Allow anonymous mappings if 'fd' is -1.
if (fd == -1) {
flags |= MAP_ANONYMOUS;
}
char* mapped_address = (char*)::mmap(addr, (size_t)bytes, prot, flags,
fd, file_offset);
if (mapped_address == MAP_FAILED) {
return NULL;
}
return mapped_address;
}
// Remap a block of memory.
char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
char *addr, size_t bytes, bool read_only,
bool allow_exec) {
// same as map_memory() on this OS
return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
allow_exec);
}
// Unmap a block of memory.
bool os::pd_unmap_memory(char* addr, size_t bytes) {
return munmap(addr, bytes) == 0;
}
// current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
// are used by JVM M&M and JVMTI to get user+sys or user CPU time
// of a thread.
//
// current_thread_cpu_time() and thread_cpu_time(Thread*) returns
// the fast estimate available on the platform.
jlong os::current_thread_cpu_time() {
// return user + sys since the cost is the same
const jlong n = os::thread_cpu_time(Thread::current(), true /* user + sys */);
assert(n >= 0, "negative CPU time");
return n;
}
jlong os::thread_cpu_time(Thread* thread) {
// consistent with what current_thread_cpu_time() returns
const jlong n = os::thread_cpu_time(thread, true /* user + sys */);
assert(n >= 0, "negative CPU time");
return n;
}
jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
const jlong n = os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
assert(n >= 0, "negative CPU time");
return n;
}
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